Dang:
There are some options that has not been mentioned that you may want to consider; aluminum engine compartment panels. They go in easier before the body is mounted to the frame and they (in my opinion) make the engine compartment look "finished".
There are also a host of little items that also effect the look (and the checkbook): original style brake cans, intake breather on fire wall, remote
oil filter bracket, the largest radiator fans ERA sells, stainless honeycomb heat insulation on the foot boxes, leather door pulls, Smith gauges, leather seats, carpet upgrades, single vs. dual rear lights, SC rear fender flare/lip, style of hood scoop, trunk mounted battery, remote kill switch and on and on...
Peter can walk you through all of these things, but you need to start out with a vision of what you want the car to be when you're done.
Jim