Let us know how that windage tray/gasket seals on start up. I bought that same thing for my 440 to use with my 6 qt pan and it looked liked those rubber "ribs" were going to line up with the edge of some of those indentations in the pan so I didn't install it. Afraid that I wasn't going to get...
When I restored my 71 Challenger I was able to re-use all of the drip rail moldings and the weather strip moldings. I had the drip rail moldings polished.
My 71 Challenger R/T which I had factory ordered from the dealer has the R/T side body stripe and came with the Challenger script on the fender but no R/T emblem.
Welcome to the site from Michigan!
The decision is up to you. How much time, effort and money do you want to put into it? If it doesn't really matter to you and you are not looking at the timeline to finish it or the resale value, go for it.