Thanks for all the advice. Here is an update for future reference.
The puppies have been in separate crates for a week now. During that time period, we have begun separate training and attention time. There has not been as much whining(either from the dogs or us ) as expected. Feeding has continued in separate rooms.
I immediately noticed an increase in 'trainability' when separated. Amazing the difference when the other puppy was not there to distract. duh, makes sense now.
Food aggression continued. They are separated by a heavy door while eating. If this door is cracked open just after the meal is finished, growling and barking ensued and the door was shut with them still separated. After a few days, I began aggressively showing my displeasure with this at the instigating dog. It only took 3 days(two with the original aggressor and one with the other to seemingly stop this behaviour. For the last couple of days, they have rejoined each other immediately after eating without a wimper.
Not ready to declare victory yet....but they are doing much better and there is now hope to keep these sisters together. I will gradually begin introducing situations which caused conflict in the past, as long as there is another adult around to break up a fight if one should occur. I need to see they are ok together, as I know I will not always be able to control their environment. One of their worse fights was over dog puke
The earliest appt I could get with the local/highly recomended dog trainer was April 22. Thinking I may be able to cancel that appt soon.