I'm thinking about purchasing a downrigger for my 2000 Gulfstream. I've been looking at the Penn 600 which seems like it can handle the job when fishing offshore. I have 2 questions, first with the Gulfstream having the full transom with bracket will I need to go with the 48" boom or can I get away with 24" boom? Second, I plan to get it with the rod holder mount, do you think I should add a backer plate under the gunnel rod holder? Any advice would be greatly appreciated.