E30 Zone

I'm not far off getting my 318i shell ready for 6 pot rightness.

I'm going to need to fit a fuel return pipe. Do I need to change the petrol tank too?

Any tips for either of the above as I haven't done it before?

no just swap the in tank fuel pump and sender unit complete from a m20 2.5 as this will have a return pipe allready fitted

No need to touch anything in the fuel department!
The 318i will have a fuel feed and return line coming into the engine compartment low down on the rear left, the same as any 325 would have. The only difference is that the four pot shell will have the fuel filter there as well, instead of at the back of the car.
This makes no practical difference at all - just take your feed from the filter outlet.

Cheers for that.

I haven't looked at this car for a while and now you mention it, yes there is two fuel pipes.

I was under the impression that 4 pots had no return despite having disconnected them myself several months ago! Is it just the 316 that has no return pipe then?