I run a 50 amp denso unit orginally for Suzuki Samurai's. Weighs 5.5 pounds. It's awesome at idle. Doesn't even flinch when you let off the gas quick in gear and rpms drop to near stall; 450 rpm. And I still run the amp gauge and everything.
There's a guy that sells them on ebay for like $99 in a one wire version and has an internal regular of course.
http://cgi.ebay.com/ebaymotors/ALTE...ptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories
Then by the bracket kit from ARengineering.com through Mancini or elsewhere. I think the bracket kit is like $60.