On my electronic carb, on the front driver's side corner, there was a vacuum port there. But it was plugged off with a different type of cap. It wasn't rubber, it was plastic and it was very difficult to get off. I tried this port after I got the cap off and it turned out to be a ported vacuum source, I hooked it up to the dist and it works great.
Some other notes on this engine lobotomy; I was able to unwind and pull all the old computer wiring out, carefully keeping the oil, temperature, and evap solenoid vent wires on the engine. Pulled the computer and all that stuff on the pass side fender off.
You can take the electric choke connection, and hook it to the white/black wire coming from the back of the alternator. That wire comes from the back of the alternator and makes it's way over to the driver's side where the regulator is located. You can intercept this wire and tee into it, and run a new wire to the electric choke to power it. The electric choke on the electronic carbs is fully electric and is designed for 12v, but the 7 or so volts that comes from the alternator still makes it work. Mine works fine like this. Having it hooked to the alternator keeps the choke from warming up till the engine is actually running.
The evap system; At first I left the large hose port on top of the carb open (the bowl vent) and the charcoal canister open. Everything ran fine, except I would get a pretty strong gas smell sometimes. The original computer system controlled this system with a solenoid. There are actually two solenoids in this system. If you find your old hose system, you can hook the hose back onto the bowl vent, and that runs though some sort of check or something and then a solenoid. You can hook this solenoid back up, you should have a connector in the harness left over for it. It just goes to key-on power. Key off, the solenoid is open and fumes from the carb go to the canister. Key on the solenoid is closed, fumes go down into the engine when it's running.
There is then a tee in the line, and then another solenoid. This is the problem, no computer means this solenoid is not going to work. What I did was take this solenoid out, and plugged in one of the very small colored plastic vacuum lines I had left over. I then ran this around the back of the carb and plugged it in the original purge port, which is the port on the drivers side rear corner of the carb. This line is very small, so it's just a small vacuum leak. it doesn't seem to affect the performance of the engine. The original solenoid used a larger vacuum line, and it only purged the evap system when the engine was ready for it. Now I do not have a gas smell anymore.