Overheating during cam break in - help

I've had all sorts of problems trying to do the 30 minute cam breakin recommended by Comp. 318 LA. Edelbrock Performer manifold. Comp Cam 262XE. Holley Street Avenger 670.

First, the Holley was flooding (secondary bowl) - I'd get it running for 10-15 seoconds, then it would flood - so I then tried another carb which also flooded, so I put a new secondary bowl on the Holley and put it back on and that fixed the flooding issue. All told - unfortunately - I had a bunch of starts and stops with the the flooding issue.

Finally, I got it to run for about 5 minutes then it got real hot so I shut it down. Put a new radiator on it today, got it to run for about 12-14 minutes, estimated at 2000-2500 rpm with a few times a little more, then it got hot again and shut itself down. Was running pretty nice for those 12-14 minutes. Tried to start a few more times, got some backfiring through the carb (a couple of fires even) so I let it sit. Checked a few things, found a leaky hose (which I fixed) and coolant level was down so I filled it up. Started it again, ran it for about 5-7 minutes (again at estimate 2000-2500 rpm) and the same thing happened - too hot, shut down, tried to get it going again, backfires, etc.

So I gave up for the night, then read a bunch of stuff on line that freaked me out, and now I'm hoping I didn't f*** up the cam.

I'm thinking about taking the thermostat out tomorrow for starters and trying to continue the break in procedure without it. I'm also thinking about spraying the radiator with water during my next attempt at the break in.

BTW: I have the stock fan, no shroud. And the temp sender (of course) isn't working so I'm not getting a true read on the actual termperature.

Looking for feedback on the following issues:

(1). Any suggestions on the overheating issue?
(2). Why the backfiring after the motor was warmed up and had been running nice?
(3). Did I f*** up the cam? How can I tell if I did?
(4). If I did not f*** the cam up already, can I continue the cam break in procedure? If so, do I need to run it for 30 minutes in a row, or am I good after enough 10-12 minutes?

One other thing - got some oil leaking someplace at the back, looking like it's coming either from the distributor to block gasket or (my worse fears) the rear rail of the intake manifold (thought I put enough RTV back there but maybe not).

Thanks in advance - I've read these forums 100s of times throughout my engine rebuild and am always amazed at how knowledgeable and brilliant - and willing to help - you guys are. And go easy on me - as I'm sure you can tell, I'm an amateur at this.