One more thing for you to consider. Since you mentioned swapping glow plugs around, be aware that, while they look virtually identical, the glow plugs for 2-stroke engines (your OS MAX .60FP) and 4-stroke engines (your Saitos) are different and the engines won't run properly with the incorrect plug. Since they look the same and have the same threads, you may have now inadvertently put a 2-stroke plug (usually an OS-8) in the Saito which should have an OS-F plug or the equivalent. Are you pretty sure you still have the original plug in the engine?