Ah...yep...thanks for the pics John...

The engine in post #7 looks like a Spitsy with the tank milled off...doesn't it?

KP...if you decide to run these engines, use a fuel with lots of oil in it...
Typical fuels for these small engines have a high oil content...higher than most modern fuels used in newer, larger engines.

A typical fuel for these small engines might have 20 to 25% oil...most of it, or at least half of it Castor...and around 10% or 15% Nitro.