Bought the Mitttelmotor part and it fit nicely.
I could not figure out why 2 of the rings, used only one and glued the rubber funnel with Sika 221
to fill tube. It's really thin sheetmetal and tricky to weld to fill tube. Also the funnel when it came
from Mittelmotor need to be fit to the fill tube. This must be originally to something else as the
inside flange is quite big and has numerous holes.https://www.mittelmotor.de
0,08214 Coil steel for the mounting funnel fills in.
0,08212 Funnel rubber for 100 l tank 914/6 GT