If you're putting it on a 3 wire plug from a Toyota, you should be able to back the pins out of the connector by bending the terminal lock tab, and just clip them into the new one.

Im still working on getting the pics up later. Emsvitil was correct, the gm pulleys are 17mm. I slid an extra I have on this morning on my way out the door for work.

I will also be replacing the cable going to the alternator to probably 4 gauge and will put a large fuse in there as well. Hopefully should be usable again by the end of the weekend.