You can still wander round the the two I know of. I think they just prefer an easy life and just crush what the punters don't pick off. Turnaround time is only about two weeks now, so you have to be lucky to find the car you need.
The other thought I had, bit like yours, was did he modify it to take a newer engine?
Quite possibly true on the mounts, mine's petrol.
Busy tomorrow, but if nobody else steps in and solves it I'll get some pictures of mine on Friday - as it is...
Some pictures of mine coming apart in case it triggers a thought. One thing I notice is that you have square mounts. Could one be the wrong height? Don't suppose they've got part numbers on that you can check?
Incomplete, but may help...
I'm baffled then, because your symptoms are what mine were.
Just to be completely clear though, you've got three things between the engine and chassis on that corner - engine bracket, bush and the bracket above?
My Richards' SIII Lightweight...
I'm not sure if it's the same as an SIII, but if it is, have you got this bracket in there. It's an extra, shown as I found it after I'd made the same mistake.
Belongs on the front driver's side.