My 1988 TC had the option of using a custom made NG tank or reusing an MG Midget / A35 fuel tank.

Here is the text from the original build handbook.

"The fuel tank is bolted directly to the floor as far to offside rear as convenient, making sure that the filler is in the offside rear corner and that the tank clears the back axle
(remembering the axle travel) and the exhaust pipe on the near side. Remember also to leave the fuel gauge sender wire in an accessible position. Cut a hole for the filler pipe in the rear corner of the floor. Bolt the fuel pump to the back of the nearside battery well, making sure that the axle cannot touch it at any stage of its travel. Connect up the fuel pipes. It is better to clip aII the pipes and wiring to the GRP floor and bulkheads rather than to the chassis as this would encourage rust."