I don't have a second base game, but if I were to imagine how I would split them, here is what I might do:
1. Print out a sheet with all the configurations, and pile the appropriate tiles on the image until you have enough of everything.
OR
2. every time you have two tiles with the same configuration, put them in two separate bags.
I imagine that that you know all of the counts doesn't help too much, as you still need to keep track of what you have.