Re: Nylon or aluminum cleats on mast?
We sail a 25 foot trailerable with a 27 foot mast that we step every weekend. I built a gin pole that has all the block and tackle and guys attached so I never have to hunt for the right lines; if I have the pole, I have the rest already attached. I used nylon cleats screwed to the pole. They don't stand up to abuse at all, at least the ones that I used. IMHO, use the aluminum.
If his lines aren't lead back then cleats on the mast are a must.