fuse blows during amp install

amp isnt worth looking into. i think he got it off ebay WITH 2-12's for $70 TOTAL. So just to make sure, for the ground, i unscrewed a bolt from the seat frame, sanded it down to the metal, cleaned it off, and then put it back together with the ground attached. Is this good enough? i don't know why this thing didn't work out of the box, or could it have been the fact that the original ground wire wasn't large enough?

No a bad ground will not cause the problem you are experiencing.  The only thing that could have caused it, (If it was not broken when you got it) would be running it into too low of an Ohm load, or a speaker wire touched ground or another speaker wire.Let's Go Brandon Brown. Congratulations on your first Xfinity Series Win. LGBFJB

Thanks, All of you, for your help