300d wvo plumbing

[dakota3c06]

I know this has been asked in the past but I see a couple of conflicting answers. I installed a two tank system, heat exchanger in the wvo tank. I put a tee on the heater hose and ran a return line to the hose with the aux pump. Do I tee into the hose between the aux pump and the water pump or after the aux pump. I ran it between the aux pump and water pump and I ran it for about 30 minutes. No heat between the engine and wvo tank but engine was at over 100 degree C. Any suggestions?
85 300d 183k