To be honest, it's a while since i've done one, but my instict tells me to fit the gimble (boat) end first, then lower the trim and it should line up/push on pretty easily, really shouldn't be a struggle. The drive shaft bellows is harder.
At the end of the day, if it comes off, no harm will be done, where as, if the drive shaft bellows comes off, or gets punctured, you wind up with an expensive bill!
"I Agree with everything you say really!" - John Cooke to Jon Fuller - 26-01-2013