All sorted. Removed all the mounts, loosened both ends of the mid section. Got the new mounts in but loose, tightened up mid section then mounts. All seems a lot more solid.
Went to fire up the engine and nothing. It has been sat a few weeks and I'd been messing with the gearboxes so checked it over. Eventually realised the battery was at 9V so put it on the maintinence charger for tonight. Tomorrow I should be able to test it out.
Small list of jobs left including checking t-box for leaks, curing engine oil leak, timing engine properly and a service. It'll get a run to Kent next week so I want to make sure it's on form.