Hi John.
Sorry for the delay in answering as i have been busy, sorting out other amateur bodges.
There are some rubber stops which you can use to raise the bonnet edge to the wings, also you can adjust the bonnet strikers to help.
Hi Simon.
here you go take tension off the spring with mole grips.
1
Crack the nut with a 17mm open end spanner.
2
3
Then use your good flat blade screwdriver to adjust.
once you have found your height or that the bonnet holds down with out being to tight to pop back up, re-tighten the locking nut.
4
5
I will be taking these off in the next few day to clean and do the little flatting of the plate to aid getting the spanner on but i doubt once adjusted you will ever need to do them again.
Puzzle now solved