i say go EFI. dont have to get all crazy with it, a tweecer will be enough to properly tune a 347. and compression doesnt affect anything as far as EFI tuning. you just have to make sure you adjust fuel and spark accordingly to prevent knock. has nothing to do with being EFI or carbed
obviously less ignition timing is needed with high compression and perhaps more fuel to keep heat down in the cylinder. put some race/high octane gas in the car. then you car start running alot of timing not being so octane limited and then it will start making good power.
to me EFI is alot more precise, carbs and EFI can make pretty much the same max power but the EFI car will drive/start and run smooth every time.
i think its cool to go to the track and see some all out gutted drag cars that are trailered there, run and idle like crap, but run great at WOT and bust of a decent time. then you have some mustang DRIVE to the track in the car, throw a set of slicks on the car, run the same or even beat the drag car, then drive home and have the A/C blasting.
BUT EFI has to be properly tuned to work best (not "calibrated" MAFs on a stock EEC) i mean either a tweecer SCT or custom chip or even a standalone. to actually TUNE your setup. once you get everything dialed in...timing adjustments are as simple as typing in the number in you want, and setting the fuel you want, no messing with springs or weights in the dizzy, no more jets and other carb stuff.
i started tuning on my car and i have had to mess with anything mechanical (related to fuel and spark delivery) i set the dizzy to 10* base and the FP to 39 psi no vac and i havent even touched them since.
old school carb guys will argue to the ends of the earth that carbs are better than EFI but they are wrong, efi all around is a better method of running an engine. IMO all the old school guys are just scared of something they dont understand.
dont get me wrong carbs work great and are pretty simple, for a pure drag car a carb is probably the simplest and best way to go. but for a good driving street car with good driving manners, EFI all the way.