Randy, (One of) my next projects is starting to escape from its 2 1/2" diameter bar also. It looks a bit like the MAN .19 (thanks to Ron Chernich).Charlie
Inside the grey cast iron bar are some brand new improved shiny OS .35S pistonsInside that little slab of 6061-T6 are a batch of new improved con rods for same Inside that aluminum bar is a cylinder lap
Randy, if you run into any problems finding backplate gaskets for the 35-S let me know, I can laser cut you some,as a matter of fact.. I have already laser cut several.