Mainly around fitting the 503 to the airframe.Mine was originally a 447 invert mount with a back to back aluminium angle setup and industrial vibration mounts hanging off the top of the engine mount..
The 503 wont clear the offside engine mount brace.Not that keen on inverting the 503 anyway,though understand its not an issue as long as prestart prop swing checks are done.
Keen to know what others are using. I will modify the original tube if I have to,but the original invert setup seems fussy. .I have a 582 sitting around that I thought of fitting,though it seems like a lot more work for probably not that much reward compared to the 503.Like the idea of the 503 simplicity,its a low hour, single carb dual CDI.With the 447 it cruised at nearly 70, not bad for this little bird.
Thanks
Mike.
