'Ramp Warrior' was a prototype that preceded the Williams/Bally merge and was later released after the merge as Midway's 1988 'Truck Stop' with modifications. We had heard that 'Ramp Warrior' was to have been called 'Diesel Demon'. We asked artist Greg Freres about it. He replies:This is a longer answer that I might not capture accurately here, but I'll try. Dan Langlois brought in a playfield that I *think* was going to be a car race theme(?). At some point he abandoned the project but the playfield was still a somewhat valid layout. Pat McMahon and I had talked about pitching the idea for Diesel Demon and Pat ended up doing some amazing sketches with a zombie-like trucker in a huge rig, with the pipes turning into demon-like characters all their own. In front of the rig was a volkswagen beetle driven by two unsuspecting females putting their make-up on whilst driving. It was awesome, but our management thought it too edgy for the truck stop locations or family arcades...plus the whole "demon" connotation was a bit much.Our then-President, Joe Dillon, decided to bring in an outside designer, Steve Kirk, to add his input to the project. Under his direction, it became Ramp Warrior, a slightly more politically-correct version of Diesel Demon, and the rest was supposed to be history...until we made the shift from Bally/Midway to Williams. The project got re-looked at from a committee of people trying to squeak out the first Bally game from the Williams factory. After the committee finished up, it was called Truck Stop and the rest was then history. Duncan Brown told us that Steve Kirk explained to him that he placed his personal design number on the backglass of every one of his games (in the order in which they were designed). Here are the ones we know: Stars has SK-1 on the jet wing. Nine Ball has SK-3 on the wizard�s cap. Meteor has SK-5 on one of the rockets. Pinstar's Gamatron has SK-9 on a launching rocket. This prototype game, Ramp Warrior, has SK-13 on the truck's license plate while the production game, Truck Stop, shows this license plate laying crumpled in the street. We don't know what games belonged to SK-2, -4, -6, -7, -8, -10, -11, and SK-12.