Great that they're enjoying each other!
Shasta was also skin and bones when she got here...very food aggressive w/ other dogs, even when we were preparing their food and ours on the counter top. We let her know that it was not acceptable at the counter tops, table, etc. and watched all the dogs during feeding. All three are fed in different areas of the kitchen and can see each other. She's been here about 6-8 weeks now and she has gotten a lot better... knows that she will eat and not have to fight for her food. Good luck! They like each other, so that's an advantage!! Congrats!!