if you've got the tools, (handy with the dremel or real handy with the drill)
just put a hole in the end of your regular PCC (where the batt would come into play), so the xl has room to fit out side of the case.....
it'll charge it, but you will have a little 'tag' end hanging out of your regular pcc in the process.
....that is of course,
if you cant possibly wait!