Geoff... I apologise if I have wasted your time..
As your posts progressed, I thought your major concern was to ensure that whoever helped you would be covered by Insurance in event of an accident.
This is why I suggested you discuss the situation with your Insurance Company.
However, it is absolutely true that chainsaws are dangerous tools and that you might be better served by getting a Professional in to do the work.
Only you can see what the work entails and make a judgement.
Best of luck..