Originally Posted by spartacus
Bill Higham Marine has some 50HP units for sale on boatsandoutboards.co.uk
From D-class lifeboats, the specification is:
1. Strengthened swivel tube
2. Gas assisted Tilt
3. Mid section extension kit and splash plate
4. Extended gear shaft
5. kill switch
Not sure if that's any help.
I can't find the information I had on them, but there are also some non standard bits related to the inversion proofing. From memory they remove the valve(s) and switch(es) related to the inversion proofing and fit blanking plates.