how to prep for paint

[Tarheel_]

own a 73 Tri mate II. The original green flake is very dull. I wish to do the paint myself using a commerical sprayer connected to air compressor.

How do i prep for the paint. I'm going from green to navy, so do i need primer? Should i spray from top to bottom?

[175checkmate]

I am doing the same thing on my boat right now. What I have been told is that a 2 part epoxy primer is needed between the fiberglass and the new paint.
Here is where I found the best price on the primer. I am also going to call them about there paint and get some information as there prices are really good. http://www.nationalpaintsupply.com/vsite/vnavsite/page/directory/0,10853,4682-123795-125102-nav-list,00.html