I've been looking at all sorts of chargers for this project and haven't liked any of the commercial options available. They are either too expensive... or too cheap. Too big, too heavy, too poorly designed or cost more than the rest of the bike. Blech.
I've been reading about a DIY, open source charger that has been refined over the last couple of years and is now available in a variety of forms from Electric Motor Works. I've been chatting with Valery Miftakhov, PhD (Physics), founder of EMW, and I'll be ordering a water cooled version of his 10kW/60A PFC charger kit.
My current plan is to mount the EMW charger on one side of a cold water plate, and the Curtis 1238 on the other side. This will sandwich the cold plate between them, and since the charger and controller will never be operating at the same time I should have no problem of ever overloading the cooling capacity of the plate.
EMW offers a fully assembled version of their charger, and I was considering ordering that. My soldering skills are frankly pretty poor. I was discussing this with some of the Dallas Makerspace members, and one of them has offered to take the time to help me with the charger build, and teach me how to properly solder. By ordering the kit, rather than the completed charger, I can put the savings (~$1000) toward batteries.