Yes, assuming 24a is as simple as it sounds.
Got the "H...EUCH" part which led to the perimeter right away. Then just a matter of finding the last few misprints. Fastest one ever.
Re Chav
To AJT and Zardoz:-
You may be interested in the Australian equivalent of "chav". It's "bogan" (rhymes with slogan).
You won't find this in Chambers, AJT! Check out the website.
www.bogan.com.au
Good for a laugh
Kookaburra