The first thing you need to do is decide how you intend to use the car. Cars guys often waste considerable time and dollars going down one path, only to reverse direction. Will it be a boulevard cruiser or on long highway drives to farther destinations? Show or go? Modified or restored? Local show trophy collector or points judged? Drive it for a season or two then flip it, or get buried in the car?
You can buy as hell of a lot of gas for the price of converting to FI. When you go to sell the car, the non-correct FI unit may even detract from the car's value.
If your car has factory 8-lug wheels, I recommend you keep them on the car. IMO there is no better looking wheel out there, and they are highly prized by Big Pontiac buyers. Roush sold an 8-lug disc brake conversion for awhile, but I'm not certain that they are still available. They required the 15" rims. Check with Larry at 815.735.4002 or lgto67@yahoo.com (tell him the 2+2 Registry referred you).
There is a company in Texas that makes 15-inch rims to fit the 8-lugs. Coker has the best selection of vintage-look tires, including a new line of radials that have that '50's or '60's appearance. Unfortunately the sizes available may not fit our cars - hopefully the options will improve. If you are not concerned about originality, go with radials. I'm forced to use reproduction bias-plieson my '65 because I frequently drag race with a FAST-class (factory-appearing/stock tire) group, and have the car points-judged at POCI and AACA. My friend has a '65 2+2 coupe which runs on radials, and the smooth ride on his car is far superior to mine.
Best of luck with your choices! Making the car your own is 1/2 the fun - driving it when done (if they ever are done) is the other 1/2.

I think I am going to leave it as stock as possible. I have my Galaxie which is more of a hot rod. I'm not completely sure what I will use this car for but I am thinking it will be occasional car shows but more for just driving around locally and some trips.

After all, I drove these type of cars as every day cars when I first started driving back in the early 70's. They are perfectly capable of going cross country with no issues. Just need to fix the carb issue, new tires and shocks and maybe check the plugs, wires, etc.

I'm not crazy about the stock shifter though. The lever is kind of short and I have to bend forward slightly to reach it. It has a little slop in it too which I may be able to adjust out. I'll have to check it I guess I have to remove the center console.

Speaking of that, the console lid is stuck shut. I tried both ignition/door key and trunk key but neither will unlock it. Not sure if it is actually locked. I can push the button down but it won't release. The lock (slot where key goes in) is sideways.

I'd post a photo but when I try they don't show up nd they are under the size limit.

Email me your photo's and I will post them.
'64 and earlier shifters are notoriously sloppy. Fortunately for us '65 & newer owners Pontiac switched to Hurst shifters.
you may have to drill out the console lock, or try picking it.

I will put in a Hurst shifter. Don't think anyone would be bothered by that and will keep the original shifter anyway. I hate a loose sloppy shifter!

Next question: How does a tire store mount and balance new tires on the 8 lug rims without a center in them? I'd like to go to 15" rims (then I can keep the original 14s with the tires on them in the garage) and a larger tire. What is the largest tire that will fit in the fender wells?

Can't help you on the tire size that will will. There's an excellent Pontiac discussion forum at this link. Try searching "tire sizes" there.
You will need to buy an 8-lug tire mounting adapter. There are several available from small Pontiac after market vendors. It is simply a flat steel plate with a hole in the center & studs for mounting the rim. Take on with you when you need tires mounted.
I bought one from Bill Coburn - he advertises it in "Smoke Signals" for $79 + shipping - call him at 303 906-4663.