Ron, I hate selfies , so I chose the photo carefully.
No, I don´t have any experience with Vincent, still rebuilding the Argentina B-Rapides since end of 80ties, will take another year or two. I´d suggest some Googling for info on LiFePo4 types, these are NOT your typical LiPo combustibles that you charge in stainless steam pressure cookers. Certainly you will check charging voltage at 14 Volt - or half of that for 6 V application. But there are lots of voltage controllers from Ebay that I will test soon, no need to just look into classic bike suppliers. Watch this place for more info on things like that.
I like this forum for all sorts of not so conventional thinking on many topics.
Vic