Howdy, yall.
Picked up an 86 T/A with 36k original miles for dirt cheap.
Problem was the tpi system was FUBAR, and I want a vehicle that isnt computer controlled anyway.
So, I did a carb swap.
Removed ALL fuel and ignition wiring, computer, and alot more under the hood junk.

Hooked up an edlebrock performer RPM, one inch spacer, and a holley 650 double pumper. Yes, I know a 650 double is waaay to much, but my buddy is letting me use it till I can get a 600 vac secondary.
In-tank pump removed and replaced with a filter,
and a 6PSI electric pump mounted in place on a dip switch. Works great.
As well as an Accel HEI vacuum advance dizzy, other than that, everything else stock.

She did run before the swap, just the computer was giving a host of issues, clogged injectors..

Wired up like a demo derby car, fuel pump ON, ignition ON, pump twice, crank and go.
Fires up fine, will rev into redline beautifully (minus a little blue smoky which im attributing to a leaky intake gasket),
but wont hold an idle at any rpm. I have to feather it or keep her WOT to stay alive.
Floats are adjusted properly, idle screw adjusted properly, carb is relatively clean, primaries are spraying (passenger front one is a little weak..), secondaries are spraying nicely.

Timing- unknown exactly. A couple degrees advanced, perhaps.
Im getting zero backfire, and she fires to life every time. Pops a little out exhaust at redline (straight manifold ending at floorboard), but hell my EFI benz does that.

Carb HAS been backfired many times, so im assuming the power valve is blown, and getting replaced.
As far as I can see, all vacuum lines are plugged or hooked up accordingly.
Theres one bolt on the intake that for some reason wont thread in, but the rest thread snugly. Riddle me that one..

So, does anyone have any ideas why she wont hold an idle?
Ive fired her up while a buddy looks at the carb, all four barrels are spraying, doesnt make a difference if choke is open or closed. She kind of just..dies within a couple seconds of letting off the throttle.
Any help appreciated, thanks