I've found it tricky today, and have one (or two) left.
1d Colour of shark, say (5)
?A?C?
The C may be wrong, in which case I don't have
10a Begin over small American prison (4)
???N
Also two I can't parse
4d Amount of herring (1000) missed by oddball (4)
I have an obscure word for a quantity of herring, but don't see the rest.
17d Parched layer carried on railway (4,3)
I have an expression for "completely lacking water", but I can't see a "layer".