Driving without throttle linkage

And what about shifting, would it be smart for me to control my shifts as well while I have this setup or let them happen automatically?
Yes, and doing burnouts and donuts all day long destroys your tires and wears down your brakes and wheel bearings, but I’ve done that, so I guess I don’t really see your point.

You gotta cut Crusty some slack, he gets moody like that one in a while. Maybe it's his time of the month, IDK.
I used to do that all the time; I mean why build a 400 hp car to idle it in your driveway all the time...... My car gets sideways every time it leaves my property, it drifts soooo nice. And does awesome figure-eights and donuts. In fact, sometimes I start it up just to go do a few of those out on the main street of our sleepy little town. I mean let's be honest, if a guy doesn't pull a few stunts once in a while, it's like not having sex for way to long.
anyway;

getting back to my 318 combo.
This 68 Barracuda was my DD for many years, cuz we were fairly poor in those years. I used to put over 12,000 miles a year on it.
Every fall, the 367 came out, and I swapped in a 318 4bbl. Then in spring, it went the other way. Sometimes the winter motor had a manual trans, sometimes an automatic, and the rear gear was a crapshoot as to what would be in it. The 367 was always a manual trans. and usually had 3.55s in it, and an overdrive.
In the beginning, the 318 had an A904, but later, I installed an A998 with the wider ratios, to get the lower first gear.
The 318 was a pure stock, freshened longblock with nothing but a 4bbl, and the TTI headers from the 367 with it's 3" full-length dual cannons.
Every winter I freshened the 367, and every summer I prepped the trans that I was gonna install in Fall. This went on for 6 winter; until one day my son made me an offer on the 318/A998 and 2800TC that I just couldn't refuse. So I installed it in his 84 D100.
Now; My Davy-boy drives like me, and that D100 spent as much time going sideways and being abused, as if I would have been driving it.
Hang on a sec:
Yes,
with the TV tied back half-way, exactly as it had been in the Barracuda.
I had tuned the governor, and reset the shiftsplits for a late 1-2 shift, and an early 2-3 shift. Thus at WOT, it hit Drive at about 60/65 mph. But it stayed in First until 5000/5200.
We put skinny 275BFGs on the back, and you know, BFGs don't have any off-the-line stick to them, but I did have to deal with the crazy wheelhop.
So,
in my case,
thru all of this,
the trans NEVER showed any signs of distress, and
I'll guess it now has over 80,000 miles on it, since last being freshened, and I myself put some 20,000 on it prior to that, as my trans of choice for winter.
Because the trans had a 2800stall, and the truck had 3.55s, and the 2.74 low-gear in it, the 318 had plenty of torque-multiplication and plenty of take-off power; so then, the BIG Thermoquad could be staged a lil later, when the primaries began to run out of juice.
Remember what I said about LOAD?
Behind your 225, the trans does not know anything about rpm. It only knows load. But your 225 does not make 318 power, nor did you mention a hi-stall. So, IMHO, I think, with the TV tied all the way back, you could chain your car to a big old tree, put the trans in MANUAL LOW to relieve the rear sprag, get the tires spinning, and then put a brick on the gas pedal and go for coffee. I think the tires will blow first, then the engine, but the trans, as long as the cooler works, will be just dandy fine.
BTW;
My Barracuda rad has no cooler; and I ran no aux cooler, since the combo was for winter-only. I just looped the two fittings together. I don't suggest that you do this. I'm jus saying that's what I did
Finally; others can say what they want. I'm telling you what I already did. And I offered OPINIONS as I saw fit, based on my experience, and whenever I did that, I told you that it was an opinion.
But here's the thing. Me and 904s are old friends. I suppose I could reassemble the main case blindfolded. And I could probably do a pretty good job of the valvebody as well. The point is that I'm not scared to actually try stuff, cuz if it breaks, I just take it apart and try again.

That linkage you are contemplating to omit, is just a device to REDUCE the harshness of the shifts when operating at part throttle, and to vary the shift-timing in accordance of your mood. In many to most cases, the first 50% of throttle travel does NOTHING at all on the linkage, as the pin just slides back and forth in the slot of the adjusting rod. That means that during perhaps 90%(depending on your mood) of the time, your trans is already operating as if the KD lever was not even there..................................

IIRC Sooke is in BC Canada. You're practically my neighbor, lol.
Listen up, I'll make you this deal;
Put an aux cooler on it, and a deep pan, then tie the lever back as far as you can stand the harshness of the shifts; then do whatever you want, consistent with the useage you describe in Post #1. If you can burn it out, over the rest of this summer, I'll recondition it at no charge, just pay the shipping. Badaboom!
Com'on just drive it!