That' s awesome that you found a coach! I assume the 50DN is going to the house batteries and not the chassis ones. Personally, I'd want to pair it with something like wakespeed W500 regulator before just bolting it in http://wakespeed.com/products.html I do not know for certain if it's compatible (obviously check with Wakespeed), but it's the route I was going to try when I upgrade to lithium. Oh yeah, we need pics!