i got a 136Amp Grand Cherokee in mine, $30 or something like that at the junkyard, direct swap just a minimal reconfiguration on the output prong but nothing major (the shield needs to be rotated that's all) - comes with the 8 groove pulley but can be used as is or replaced with the 6 groove one, i didn't bother swapping it. There's a good writeup in the FAQ with part numbers and all for various options, there is a 150 amp or so OEM listed in there that works on YJ, can't remember which vehicle comes out of but didn't find one at the time so i went with the GC one instead.