Picked up a used 750 Mighty Demon... where to start?

If its used off a running car and you talked to the guy, you got a deal. So many times guys pick these up off Ebay from a guy that got it in a "trade" or "a bunch of parts" and never ran it. Probably because it didnt run good at all, lots of QC issues. But then you find a peach and all is well. Don at 4secondsflat.com used to sell and support these but BG went under, reorganized and came out with the TQ "cube".