I haven't seen the intake you are referring to, but I can tell you what the heater is for and maybe that will help.
Factory /6 intake tubes are long and made of cast iron, and run horizontally. This makes starting then sometimes difficult, but more importantly, the engine would run like crap during the warm up period, if it wasn't for the fact that the intake sits right on top of the exhaust and connected to it, to warm up the carb and the air flowing thru it. Once the tubes warm up, things get a lil better. As carbs got ever leaner back in the day slanties needed help.
Now along comes Terry and divorces the intake and header and loses the heater. And worse is now the runners are aluminum which suck all the heat out of the passing air, and some of the fuel fails to enter the chamber, instead puddling on the floor of the intake. Because this leads to the engine wanting to stall, you blip the throttle, and the plug gets smacked with liquid fuel. And so it stalls anyway. So then you twiddle the choke and ol slanty is buzzing along for 10 minutes on fast-idle, trying to warm up.
That sucks.
So Clifford offers an elegant solution, the intake heater. What you do is take water from the hottest part of the warming up engine (recall that the stat is not yet open), and send it to the intake, where it's gonna heat everything up so the fast idle can be kicked off hopefully in a minute or two, and then you can drive away as the runners suck that heat out.
Ok so now that slightly less hot water gets taken to your heater core, so you can warm up your toes on cool days,and keep the windows defrosted, Then it gets returned up front and sent back into the waterpump for another trip around the block. Eventually the water in the block will get hot enough to open the thermostat, and after that the hot water goes to the rad. But the waterpump is still pulling the water in from the heater core so your toes can continue to be warm.
After this, the cooling system efficiency determines how hot that slanty is gonna run. The stat only sets the minimum, and helps the engine to warm up quickly. If you remove the shroud or the fan, this will reduce the efficiency of the cooling system and the engine will run hotter. If you swap out the 4-blade fan for a 5 or 6 or 7-blader, this will increase the efficiency, and the engine will run cooler, perhaps down to he minimum , and if it over cools, then the stat will close again.
Ok that is the theory, except let me add this. It is entirely possible without the heater for the carb to run so cold during the warm-up period that icing can occur in the venturies. Icing is when water vapor in the air, freezes in the venturies, due to the loss of pressure . When this happens the ice can choke the air and or fuel and the engine will stall. By the time you get the aircleaner off and are able to look down the carb, many times the ice has melted and you have no clue why the engine stalled. So you put it all back together, hit the key, and it fires right up! Daymn. only to stall again a few minutes later. This is extremely frustrating.
OK so now, all that remains is for you to plumb your system.
IIRC the hottest part of your cooling system is the front of the head, and a hose should already be there going to your heater core. That hose I would re-route to the intake heater. Then you would have to run a new hose from the heater core, to the other nipple on the intake heater. Badaboom. I won't say it doesn't matter which hose goes where on the carb heater, but I doubt it does. If you have a choice as to one is higher and if it is convenient, then I would hook the hottest hose to the lowest port; but I wouldn't hesitate to run it any old way, that does not interfere with the throttle cable..
Now here's what's likely gonna happen;
around town, the engine will heat up past the thermostat set-point, heating the carb and the manifold and everything is gonna magically work perfect. As you hit the hiway, ram air is gonna lower the temp of your cooling system, possibly to the minimum set by the stat, and the carb/intake are likewise gonna run cooler.
And when you floor it, the engine is gonna rev up and pull air thru the rad and the engine temp will fall, then ram air is gonna take over keeping it cool. Then as the engine begins to work in second gear, the water temp is gonna start to rise again, slowly, cuz ram air and rpm are working together.At the top of second gear with 3.23s you will be doing about 80mph, and the trans goes to third gear. Bam instantly the Rs will fall to ~3400, and the engine more or less says g'night, but if you stay in it, the fan is now not helping at all, . Thankfully ram air is ever increasing, so somewhere along the way, the temperature is gonna stabilize.
Here's the first thing, until you hit third gear, the air is flying thru the runners so fast it doesn't have time to heat up. When you hit third gear, acceleration is gonna fall markedly, and the engine will be working hard. But this only lasts for a short time cuz if your slanty can do more than 80 in the quarter, she's pretty "hot".
And the second thing is this; factory gauges are so slow to respond that I doubt you will see any of this going on. And it does not matter, you can't change it, unless maybe you have a monster cooling system..
' course this is all off the top of my head,lol.
As for the fan-sensor not fitting I bet it's for a GM, lol. You might have to contact the manufacturer for a substitute. Alternatively, you might have to figure something else out, which usually involves drilling and tapping. What you don't want to do is stack adapters, and end up putting the sensor in a dead space, which I have seen run 10 to 15 degrees cooler than the water below it, just an inch or slightly more away.
If you have room for a mechanical fan, I see no advantage to running electrics. The most efficient and reliable street systems I have seen, are mechanical; and before you rush into the horsepower argument, think about it.
