You fabulous people, easy when you look. This has helped me fill a few more in.
I have a few more now unsure of:
1d Giving head in german city, the result of drinking nine pints of Stella, three brandies and a bottle of blue nun? (8) ?A?G????
21 / 3d Something for second course in Kent, group sex for seniors (6,8)
S????? / ?A?D????
16d /25a Get away with wobbly tits and minge - it's bongo literature! (8,5) ??O????? / ?????
24a Aristotle shit-faced - you bet it's the system (9) ??????S?R
18d Close deal that's set up for a pre-rumpypumpy last tipple (8) ??????A?
19d Car's left with noxious excrement for starters i'd stashed in rear (8) ??????D?
and finally 20d More than one giant article found between knockers (6) T?????
Thanks again you fabulous people