return fuel line issue..outabox thinking required

need to make new return line of larger dia to tank..cant use oe return fitting on tank as too small and too old to try and remove ..

so need to think of (and fecking quickly) a way of making new return into tank..needs to be 8mm id pipe dia..

car is 1971..tank is good,but only has sender and oe return..no other holes to use..except breather and filler..

though of using breather via a tee,but not happy about that.

DO NOT want to drop tank..nor weld a tail in etc.

any ideas??? thanks

If your not going to drop the tank or weld a new fitting then your options are very limited. Can you do something with the sender unit? Maybe add a fitting to that. Otherwise it's the filler. Just one thing. You have gone to great lengths on the rest of the car. Why won't you buy a new tank and weld the tail and do the job properly? I can understand the costs but after all you've done it would be just a little job in comparison