Modded cars seem to trade at a discount for the most part.
I had my SC listed at $35,000 got many calls. Quite a few telling me I need my head examined. Also quite a few
not squalking at asking but much more concerned with the originality and documentation.
As it were I realized I could not replace the car thus I decided to keep it, walking away from two offers north of $30,000.
Here is a bud's Modded SC......
http://forums.pelicanparts.com/porsche-cars-sale/805939-fs-1983-911sc-3-6-varioram-hot-rod.html
One of the best set-up cars I have ever driven...