You're probably going to need to get under it, and have very narrow hands. The filler plug is adjacent to the passenger footwell box, so you could try as I did, drilling a hole in it and getting a socket on the plug, but working on my back in the footwell does make me want to puke
From underneath it's easier but there isn't much more than 2 " I guess to play with, so the filler plug comes out ok, but getting it back in is interesting if you havent drilled the hole.
If your mileage is that low, I'm not sure that you need to be concerned anyway, the oil should be ok, although you may need to top it up. Mine was done for the first time this year in at leat 10 years I think, with greater mileage than that.
Windscreens... They're for poofs