Go with whatever color you choose or require because just about everything you buy will be "Black: Paint to match."

If you want to split hairs, it's a totally different chassis between the w/w/o fold down seat. You can rig it to get a fairly decent fit, but nothing like the chassis designed for the fold down.

I won't bother explaining what it takes to make the conversion because you are going to have to find salvage parts and weld them on your car. Now that Terry is dead, all I can say is good f/ing luck finding someone who knows about these cars rather than talking about these cars.

If it were me, I would keep the fold down even if I didn't like it because it looks fine when locked in place. Just keep in mind that swapping from one to the other isn't simply a set-in-place installation.