Replaced the Chinese vacs with new 5.7 's and related modifications to make them fit the heat coils, hooked up a 3rd cord pigtail for the heater so it can avoid blowing breakers, pulled the pumptec and stuck in a Cat pump, installed a fan to cool off the pump motor. I'm trying to figure out a way to run the vacs in parallel instead of series. Any ideas? I'll post pics tomorrow.