89' pimpscort alternator/power problems

I was away for two weeks last month and my alternator died. It has a new battery and I went to an auto yard and got another alternator....
I think the amp for my old one was 68, the new one is 75(I think thats what the dude said,) but he said it would still work fine. I went home, installed the thing, and when I went to jump my battery I hooked everything up and when I tried to connect to my batterys positive, an ungodly amount sparks went a flyin (I've jumped my car many times and know that sparks fly....but not like this!) and the battery started smoking like crazy. It doesn't take a genious to realize that something is very wrong, but at the same time, I have absolutely no idea what the hell is going on!!! Anybody have any tips or isight into what the problem is??!?!?!?!

Oh, I forgot to mention something...When I try to jump the car, there is absolutely NO juice going to the car. No dash lights, no door ajar lights, no noise at all when you turn the key....nothing.
HELP!

Is it the starter selinoid (relay)? It should be on the inner fender near the battery.

You can trace the hot wire off of the battery to it. It will have either 3 or 4 terminals. Their less than $10 at an auto parts store.