When I raised the roof on my 4905 I replaced all the aluminum from the about window level up.
All of the old aluminum with aluminum rivets and the steel with aluminum rivets only had ANY corrosion or rivet failure was where there was water intrusion and/or rust.
I used the shaved head rivets as I wanted to match the bazillon rivets that GMC put in.
Lucky for me I only had 3,000 to do.
I have never had a problem priming aluminum also, as Brian D. said "Follow the manufacturers directions.Cliff