For me this is a little bit paranoid
Both myself and a far more experienced mate have been running Series 1 V8s for years (more than 20).
I have broken a layshaft twice both times when taking it easy.
I am notorious for caning cars and my LR is no exception, as to my mate, he may be a little older, more experienced, more reserved but then again he would drift it with a caravan on the back so maybe not.
If you run 7.50s then I don't see a problem if you are running bigger tyres then yes.
Marc.