Lenny, IMHO, there is a bit of a fallacy out there with doggies and that is you need go up in gear to maximum power. No angler I know is capable of holding onto a very heavy outfit on very heavy drag against a huge doggie that is determined to go in one direction and prevail. With big doggies, we tend to land the stupid ones only. By no means am I denigrating some of the captures of really big doggies but the reality is that if you hook a really big doggie in deep water and it decides it is going in one direction and one direction only, it's a goner. The only ones we land are ones that swim all over the place in every direction.
I've found in the past that there is but a marginal difference whether I am fishing PE6 or 8 or even PE10. The fish is going to swim wherever it wants to. If anything, really pulling hard on them seems to send them berserk and then they fight crazy hard, literally running themselves to their deaths. The trade-off then is whether you're better off with more line to allow the fish to swim all over the place or the addtional pressure you can apply with heavier braid. I can tell you that going heavier on doggies didn't work for me - at all. About the time I stopped fishing for doggies, I was thinking of going the other way and that was back to PE6 and playing it softly, softly with them. Incidentally, I got an OH55 specifically to dish out some punishment on big doggies. I sure taught some samsons a lesson with that rod but the only thing that rod achieved with any decent sized doggie was I started crying for my mummy a lot earlier than I did with my Nirai or Fremantle.
As for overhead or spinning, only you can make that decision. The best jiggers I have seen like Yoichi Mogi, Dave Irving or even Tak Otsuka locally all tend to use overheads for some reason. I'm too damn uncoordinated myself.
I think Eric's idea is a good one - head out for a charter with Al and try out what it is like.