It feels as though continuing this thread is more appropriate than starting a new one.  My son had a lot of problems with the LH drive shaft bottoming out when turning right on his 205 when racing it last season.  Massive vibration through the car - like rumble strips X 100.  It is fitted with 309 wishbones, and 205 driveshafts (which we changed twice to no effect).  The drive shaft plunge measures only 3.5mm on the near side, well below the 10mm minimum we have been told of.  We tried moving the engine as far as we could to the right (off side), but could only move it a mm or two, so no noticeable difference.   Over Christmas we have had a chance to remove the engine and subframe.  One thing we have found is the gearbox mount looks damaged.  Can anyone tell us what type this is?    It comes with spacer I have shown in the second photo.  I'm guessing the spacer will lower the engine - good for lowering the CofG - but bad for drive shaft alignment?