Thanks but the C in R?CH comes from:
14a Embrace pilot fixing old car inside , for which I've put accolade - ace being the pilot round ol(d)car - "d" being the extra letter???
I have completed grid and have instruction.
But don't understand which 2 letters need inverting?
And then which 12 letters need highlighting?
Surely its not as simple as highlighting the first column!
Any hints appreciated