Alrite so heres what I wanna do. I wanna mount my amp on top of my sub box. This is gonna be easy but the only question I have is my ground wire. I know its not supposed to be any more than 3 ft from the amp. So would it be a good ground if I hooked it to the bottom of my seat or would that be bad. If you have any suggestions please let me know.
its best to ground to the chassis, and most seat bolts contact the chassis (maks sure to sand away any paint on bolt and keep carpet out of the way) so they usually work. and most cars are unibody now, so bacially, where ever you can ground at is where you have to.
Altho shorter/heavier runs of ground/power wire is always better, electrically there's really no difference between a "long" ground wire and a "long" power wire. Just keep your runs as short and as "thick" as you can. If you're worried about the length of your ground just use heavier gauge wire. Four feet of 4 gauge wire has about the same resistance as one foot of 10 gauge.