The engine design is such that I would highly suggest running a low nitro glow fuel with 20% castor oil in it, no synthetic oil or blends. 10% nitro is probably a good way to go.

K&B used a couple three different carbs on the engines over the years.
The Perry Carb was quite popular for a long time.
it has a brass disc opposite the needle valve you use for setting the idle mixture. But you seldom needed to mess with it.

K&B later used a carb of their own on the engines. Like shown here for example on the .65 engine.