Looking for a used good condition Electronic Control Panel for my 1996 Hydrodyne Grand Sport XP Comp Elite 5.8L 310HP PCM
They don't often fail out. Depending on what your symptoms are, you may fix your problem by just systematically going through all your electrical connections (especially the grounds), clean, tighten, (dielectric in barrel connections), etc. I don't know that I ever really see used ones come up, and new old stock ones are pretty pricey. You may also get some more help/guidance at either the planetnautique or correctcraft fan forums, given the huge quantity of GT-40's in the nautiques over the years (especially compared to the numbers of inboard dyne's that have that engine).
