On later cars, MMC de-centred the rear wheel w.r.t the wheel arch, I’m not sure when this occurred (introduction of long door cars?)
A consequence of this was that Mulfab (and maybe others) produced an aftermarket centring block that moved the axle back.
After a number of years, MMC hit upon the idea of relocating the mounting pin further backwards (date when?). Since then this is the spring format that MMC,and others produce to.
For any car with Girling back plates and a rod operated hand brake this current format of spring will have an interference between the the wiffle tree and the fuel tank. For those with Lockheed brakes with cable operation this should not be the case.
The work round is use a Mulfab centring block and use it mounted through 180 degrees to push the axle forward. It will all appear obvious when the new and old springs and their respective distances between the mounting pin and front eye are compared.
A side effect of the above work round is that the rear will be slightly lowered.
As a separate question, when MMC moved the spring mounting back: did they change the geometry of the rear roll hoop or just expected compliance in the shock absorber bushes to take up any gap at the top mounting pin?
