I removed the gear case cover to paint it, I am now trying to put it back on. Following the manual I lubricate the bushing and try to push it back on straight. I can barely get the cover on the cams before the bushing start binding. Is there a trick out there to re-install this cover easily?
I would try compressed CO2 to freeze the cams a little bit, but that wont react very well with the oil I used to lubricate them.

 

As long as you didn't take out the bushings or anything like that, it should just go back on. It needs to be very very straight, however. It could take some effort before it will finally get back on.

If you had the bushings removed, then it's very likely that they are aligned wrong and/or need line reamed to fit the cams and align with the engine side bushings.