Directly in front & above the charcoal canister (the pipe connector end) there's a bolt hole in the chassis box section - what goes in it? I may or may not have removed something from it - either way, I've forgotten.
For those who have never seen it, the charcoal canister is on the RH side of the car (underneath), just to the right of the spare wheel well. Three pipes connect to the front of it. The hole is just in front of them and above. Petrol cars only (I think!).