Quote:The camshaft is in exactly the same spot for all A series engines [in relation to the crankshaft centerline] & the A14 cam will physically fit & work in the 1200 & A10 engines, ........... but,

The early engines drove both the oil pump & the distributor from the same drive gear near the front of the block/cam.
Engines made fron 1974 had the distributor moved further back, so a second drive gear was included on the cam casting. This gear is, coincidentally, located exactly where the fuel pump eccentric for the early engine was located & the newer engines have their fuel pumps located elsewhere along the side of the block.

If you fit the A14 cam to an early engine, the forward drive gear on the cam will happily drive both the oil pump & the distributor while the rearmost drive gear on the cam will no longer be used.
You can not use a mechanical fuel pump since the second drive gear has replaced the earlier fuel pump eccentric so you will need a blanking off plate & an electric fuel pump.

The fuel pump eccentric on the A14 cam will no longer line up with a hole in the side of the block so, like the unused drive gear, it too will have become redundant.

You can not use an early cam in a late block if you want to run a standard type ignition system as there is no additional drive gear on these earlier cams to drive the distributor.