It also fails to mention the engine oil quantity, which I find a little disturbing.
Itīs 5.5 quarts or 5.2ltr
Are you converting to turbines from Piston? Itīs normally not a issue on turbines how much oil they hold, they usually donīt burn any or veryvery little needs to be added.
BIII s/n 3562 and subsequent have the 91USG tank and Iīm pretty sure a range extender cannot be fitted. It would be pretty useless anyway since you could only get some 5.0 USG more into the tank.