How tight a fit did you have you could have relieved in the centre would make it easer to get in with full size engines we always finished machined after fitting.
John
The size I attempted was .003 if I remember correctly.
I think that the finish is what gave me the most problems though. I also don't have a press to make life easier.
Making pretty holes isn't in my skill set yet =)
I will eventually give it another go on another build. Most likely a single cylinder engine at that point.