NIce car. Just needs a little TLC to "shine" again.
Any mods should be consistent with what the car COULD have come with from the factory. Cosmetic or otherwise. 15" Magnum 500 repros (probably 15x7) would be a good upgrade, along with radial tires (whitewalls are still out there! either 14" or 15". just have to look or go to Diamondback tires).
Add some HD shocks and get the brake system condition verified. Replace ALL of the rubber fuel lines, tank forward. Get it tuned and ready to roll. Fix the body work and possibly a repaint in the orig color (which was popular back then). TLC and cleaning/waxing. Then ENJOY it before you do anything else.
The recommended torque converter (probably has the 11.75" converter, but the 10.75" converter came in "low stall" and "high stall" variations). A rebuilt 3.23 "chunk" can be over $500.00 and the reman converter can approach $200.00 . . . PLUS labor.
Personally, I like the way the 383 2bbl /2.76 axle runs on the highway. The natural cruising speed for my '66 Newport was 75-90mph. That keeps the rpm on the meat of the torque peak, 2bbl or 4bbl, in the 3000rpm range, plus or minus a few hundred. At 70mph, it's "bored", but as soon as it cracked 75mph, it started to feel "right" and was enjoying itself. At 95, the ride started to get a little "busier", in comparison. Just how the harmonics of that car were! 3.23s would put the rpms at 3000rpm at 75mph or so. A shame to have the engine running faster at those "fun" speeds, to me. Especially on a 2bbl car.
Value? Any car is always worth more to the general public "all stock" or upgraded with stock-spec parts. No big deal with the OEM electronic ignition kit. Of a newer Edelbrock 4bbl in place of the OEM unit (4bbl). Get much past those easier bolt-ons and "return on investment" diminishes, typically. New basecoat/clearcoat paint rather than the orig "single stage" acrylic enamel would typically not be a big deal either, as it's higher shine is what many expect to see now, although it's technically incorrect in some orientations.
When you start doing non-stock/OEM modifications per se, you can limit the number of potential buyers, later on. They might be neat to you, but finding somebody with money with the same orientation gets to be "the trick". Best to keep it "stock" with year model correct upgrades, other than what I mentioned earlier . . . for the best return on investment.
A side issue is that any later owner can have a decent degree of confidence in getting parts for it, later on, from the local auto supply or similar. IF you do change something, put the repair order in the glove box or other "safe place" for future reference . . . YOURS' and possible future owners benefit.
All things considered, ONE thing I'd put on a priority list is a new timing chain set. Many times, the plastic teeth on the stock cam sprocket were in the deterioration stage by 80K miles. You can put a stock one back in, but a roller chain will last longer AND can be bought via Mopar Performance. Otherwise, a Cloyes Plus Roller will do the trick. That's cheap insurance, to me, as one engine I have, I did the Cloyes upgrade and that chain's now got over 400K miles on it. Douse the chain and sprockets with assembly lube at the time of installation, as there is no direct lube to that area of the motor . . . all "splash".
Get the car cleaned up and "investigated" as to what's there and such. Drive it and enjoy it to "baseline" things before you do any changes/upgrades. Prioritize things as to what you do when and why, for good measure.
Just some thoughts,
CBODY67
