fun thread.....
following along and lurking intently
btw....... I am about 90% sure the K&B 6.5 and F-1 engine has the same mounting holes as a ST X-40 engine. Which, in that case, means its the same bolt pattern and footprint as the Jett and Nelson F-1 and FAI engines.
I will have to check, but if this is the case, it would mean you could swap out the engine for a jett or nelson at any time in the future. Makes starting out with your current engine and upgrading the engine later a whole lot easier.