Are you trying to mate up with the existing holes in the hull?  If so, I wouldn't even think about trying to do that.  Fill in the old holes with RTV or resin (if you want).  Pick a starting point for the rub rail, and just drill the new rub rail on 6" centers, offsetting them about 3" from the existing holes in the hull.  Do this before you start attaching the rub rail.  Rivet (or screw) the new rub rail as you wrap it around, drilling each new (hull) hole as you go (you did drill the rub rail first, right?)

Make sure that you have a couple of feet of material for "leverage" around those sharp corners at the sponson tips (or any sharp corner).  Once you get the rail moving around a sharp bend, you don't want to stop, because the material will be work-hardened, and it will very difficult to get it bending again at that same location.  That's the worst part of the whole process - wrapping the corners like a madman.

Good luck!

here is what i am working with.....

I want to change mine also, looking at the vinyl. Advantage is using on their new boats.  I have an 88 Advantage classic. I could use some input also

Please keep us updated on your progress.  My project boat looks like it smacked the dock just hard enough to distort the rub rail in one small area.  I hope to get the boat painted next month and will be pulling/filling the rails.  I'd like to change out the stripping when it's done too.

I want to change mine also, looking at the vinyl. Advantage is using on their new boats.  I have an 88 Advantage classic. I could use some input also

Hey caddy, here's what our Advantage looks like with stainless.
Just another option