Header Tank ?

[BadRedWedge]

Do I need two returns to the header tank (upper and lower) or could I just do a 2 into 1 and save some pipework ?

[TVRleigh]

Not sure,
But the V8's and Rover SD1 IIRC only had one. return. so I think you could do a re-desin and remove some of the hose'es, esp if you remove the hot spot from the Plemum.