Going back to the original first question in this thread about the front and back of the mowing deck being out by a bit.
Today I fitted a new chain to the rear drive and believe it or not the problem seems to have been resolved or improved. The chain adjustment on this model Greenfield is done by pushing the rear wheels down as the chain stretches effectively raising the rear of the mower. The old chain was that bad the adjustment was at the end of its travel. The new chain I installed today has obviously completely reversed this as the wheels are now pushed back up as far as they go, lowering the rear of the mower. It has levelled the deck out somewhat.
The simple things eh!!