I had given a passing thought to the 4BT, weight would be a major concern though. Then I thought about maybe a 3BT or perhaps a 1.6 or 1.9 VW diesel, something lighter. I'm not sure if the small three cylinder diesel tractor engines would have the oomph to get up to highway speeds. For now I'll just play with it as is, maybe wheel it a little and then restore it to "Parade Princess" status.