This probably isn't too helpful, but when I bought my K5, I had it flatbedded home (not licensed, so I just decided to pay the $55 for the tow). Better to just not get pulled over with no plates, even if it'd be legal for 30 days after purchase with the title and bill of sale.
Anyway, the driver got his way-huge rollback transport (for towing straight trucks, it looked like) to the pickup site, backed into the lot, got out of the cab looking worried, and asked if the Blazer ran ("sure does, like a top" I grinned). He looked extrememly relieved, probably because it would have needed some sweaty up a slight grade pushing if it was just a roller).
He rolled back and tilted the bed while I started it up and drove the K5 from its parking spot to to the hookup area. He looked under the front end and said "oh, that's nice!" because there were 2 hefty frame-mounted tow hooks (factory, RPO V76) for his big bed winch cable to yank on.
He winched the K5 up the inclined bed, leveled the bed out, went to the back and hooked two bigass chains to the frame rails (existing holes from factory transport hooks I'm guessing), cinched down the winch to put a heavy load on my leaf springs & squat the K5 down, and off we went. Reversed the process at the destination, paid the man, and that was that. Very quick, very secure and stable.
Well, that was kind of wordy and rambling, but those 4 attachment points gave great service.
