The 206K-4 engine is basically the same motor. The only differences would be the oil pump, the rear main seal and the original water pump would have been lowered to be in the same position as on power units.
If you are get the motor and would like to put an original style oil pump and filter on it, I'd be interested in getting the 206K oil filter set-up for my 2 Star. I really just need the filter and filter mounting bracket.
It would be interesting to know what happened to the 2 Star Crawler.