replace relay in boss amp possible?

Well, yesterday I had some time to kill so I decided to check out this problematic amp/wiring situation. My cousin and I picked up a cheap 40 amp relay to test the theory. If it had worked, I would have ordered the TYCO relay and put it to work. We get to his house and I take a look at the amp to see what we're dealing with. Mind you, I saw it once right after his buddy installed it and I was so appalled at the power wiring I never looked at anything else. The first thing I notice is 12+ is jumpered to the remote terminal on the amp. Called up the installer who was under the impression the amp wouldn't work without this jumper. Don't ask me what he was thinking. So, we pulled the jumper, confirmed voltage drop on lead, verified correct operation, made solid ground, installed toggle switch and blew the fuse. It was working fine before finishing up so I think he must have shorted it when he was closing everything up. Amp fuses were fine. I'm buying him a circuit breaker and telling him to never let his buddy mess with his truck ever again.

Your last sentence is the problem solution. But another example how (the luxury of) inspection can solve and prevent a lot of stress, time & money. Luxury! Ain't it funny what people do? (NOT!) "Oh, I thought...". But thanks for the update and the close. Happy Graduation!