Here is an issue I just had while replacing my 50 SX with a Saito 91:

The owners manual says to place the engine so that the black plate of the spinner is 5 inch (150 mm) from the firewall. 150 mm is just about 6 inch, not 5. When I mounted up the 50 SX originally, I didn't catch the typo in the book, and mounted the engine 5 inch out from the firewall. Everything seemed to mount great there, but the engine cowl was mounted about an inch too far back (the graphics didn't line up well). I think that the book meant 6 inch from firewall to spinner, but there is no way that the engine mount that came with plane is long enough to extend the 50 SX out to 6 inch. Has anyone seen this problem? Is there a way that stock engine mount can even get an engine out that far?

Thanks,
Rob