BMW Repair: fuel leak, 1986 bmw 325e, bmw 325e

Question
Hello Don
I have bought an 1986 BMW 325e with my dad. M20 engine
VIN WBAAE5406G1690416
We have a gas leak which seems to come from above the gas tank, or it may be the tank itself. We are trying to get the tank(s)off.
The drive shaft needs to be removed.  We have the bolts in the back off. Centre can be loosened, brackets off. Bolts towards the front near transmission are loose, but don't come off. Do I have to lower the transmission too yet? Ouch.
Or could we lower the drivetrain in the rear? Other ways?
Thanks for your attention. Much appreciated.too many mechanics are chickens when it comes to real cars.

Dave

Answer
Dave I have received your question and your headed in the right direction to removing the tank,you won't have to pull the transmission,or lower it.Before i go into the removal I have a question first.You said you think it is coming from the top of the tank.Have you check the sending unit or the hoses going to it?You gain access to that by removing the rear seat bottom.Once removed there is the cover,remove the screws and check it out.The senders often corrode until they leak and its repairable without taking the tank out.I haven't seen many tanks in 3 series that would leak,I have them sitting around here for years and they don't leak.