Battery Light Came ON

It may just be that something didn't get reconnected or that it came loose while moving stuff around. Check the stator wire for the alt and make sure it's getting juice.

Yep. First off, I would NOT do the disco' test that you did - the resulting voltage spike from the alt can harm computer components. Future reference (and when people search and see that someone did that, they think it is ok to do, which it is not on an EFI car, IMHO).

Do you have a 3G alt (I saw dual fans which made me wonder).

I would make sure the switch-and-sense wire is still attached to the solenoid-side wiring of the alternator cable. And accordingly, if you did anything with the stock voltmeter gauge, that wire needs to be connected for the switch-and-sense to work.

I still think Daggs is right on - just cruise over what you did and you should see something.

BTW, there is a fusible link on the alt cable, but when you did your test, had you blown that, I dont see how the car would get juice to keep running (with no alt input, in essence, with no alternator power to the electrical system).

Good luck.