Yeah they say they are. If they were in a rover packet I would believe them.
Too tight will not work either so measure carefully.
If the ratios were altered you would almost certainly only do the driven.
The drive is too hard as its two pulleys in one. The driven pully would need to be made smaller. Well assuming you want faster rather than slower.
The pulley on the deck would be cast or machined of some sort. The pulley on the motor and the one on the box are fabricated from sheet steel. If the raitos had been altered i would expect the replacement to be some sort of modified over the counter pulley.
