If you do attempt this, I would suggest getting the Potter's first, and making sure that it is adjusted and eating prepared foods before adding the flame. IME with Potter's they are fairly shy at first and changes can cause a hunger strike.
I currently have a Potter's and a Multicolored in my 58. The Potter's was in the tank first and is smaller. I put the multicolored in a little breeder's box for the first 24 hours, so the potter's could get used to it. Once released there was some minor chasing, but nothing major, from the Potter's. Heck, my mated pink skunk clown pair caused more issues.
They have been together now for about 3 months and don't seem to care one way or the other about each other. Even at feeding time there isn't any issues.