What doesn't it like about your fill hole? They don't use any vapor recovery stuff on the diesel nozzles (or at least they didn't from 2004-2006) and on side-fill tanks, the diesel shoots right down the gullet. Even the enormous semi-truck filler nozzles seemed to work well for me, so long as I paid attention to reduce flow as the tank neared full.
As a side note, when I've borrowed someone's military 109 (petrol), I never bothered to raise the filler neck because I have a fuel nozzle attached to a gas station fuel pump and its pretty easy to shove that nozzle in the hole down there without making a mess. To my knowledge, that filler neck is only raised when you fill from Jerry cans so you can begin the pour without spilling fuel all over the place trying to hit the hole way down on the tank.
--Mark
1973 SIII 109 RHD 2.5NA Diesel
0-54mph in just under 11.5 minutes
(9.7 minutes now that she's a 3-door).