Do you see a nice cone of fuel spraying from both TBI injectors? The plugs are chintzy garbage, and the wiring gets old.
If you're set on a carb, I won't dissuade you. I'd run the red fuel injector wire to the electric choke. It stays hot so long as the key is on. You can use the stock small cap HEI with a single wire if you just want locked timing, or you can swap in a large cap HEI and run the power wire from the small cap right to the power input on the distributor. Tape off all the extra wires and connectors.
A TH400 will need a vacuum line to the vacuum modulator. It will also need a kickdown switch on the throttle somewhere, and that will be a DIY project.
A 700R4 will need a TV cable. I can't remember if the '94 has a spot for it on the throttle bracket. If not, go to the treasure yard and get a '88-92 throttle bracket and cable. You absolutely cannot run the 700R4 without it. You can adapt the torque converter clutch to work without the computer - a quick google search will give you dozens of links on how to do it. Note that earlier 700R4s need a 3-4 pressure switch added to the valve body, but the late 700R4s/4L60s have it. Run a hot wire to a TCI vacuum switch, wire that switch in series with the 3-4 pressure switch, and bam!, you have TCC lockup.
One more note on TBI vs carb:
Lack of power everywhere/bogs down while idling
If you're bogging down while idling, you have an issue to diagnose and fix. If it ran fine but bogged down with heavy throttle application, the TBI is inadequate and it makes sense to switch fuel systems.
My cam specs:
Lift: 0.507 int./0.515 exh.
Duration @ .050": 211 int./219 exh.
LSA: 112
The factory TBI ran great - until half throttle. It didn't flow enough fuel, even after I bumped up the fuel pressure. The tools to burn new chips cost half the price of a Holley Sniper (at the time). I went Holley and fixed all the TBI problems, and then experienced Holley problems.
