Word of wisdom: Something is valuable to only those who know how valuable it is
I'd also suggest you either try enthusiast forum, or take parts out. Only enthusiasts would realize the value in those mods.
For average Joe, on the other hand, most of them wouldn't realize the value of the mods. Not only that, some might even take the word 'modded' as the same meaning as 'abused' or 'riced'. For them, most of the mods won't add value to the car for them, in fact, they will concern about the mod and either they will walk away or try to negotiate the price down because of mod is a sign of the owner's abuse for them. Many people (probably most) like stock/OEM condition when they buy used car.