Engine and Transmission Tech

Forgive me if I have placed this in the wrong part of your forum. Please move it if required.
I have spent the last couple of years rebuilding an old a series 2a Land Rover. When I bought the project I had every intention of removing the scruffy looking Rover V8 and finding an original 4 cylinder to put in. In a moment of madness I decided to keep the V8 and rebuild it. How hard could it be? Well things have been going very well up to now. As space is limited in the Land Rover I have gone down the route of fitting a shorter water pump from a P6 Rover V8 and matching crank pulley. In fact I've gone one better and fitted a new Buick water pump and appropriate pulley. On fitting the crank pulley I have noticed that the groves do not line up on the pulleys. Initially I thought I had made an error in fitting the Buick pump but on refitting the old P6 pump the misalignment was the same. What is the problem? I thought at first that I may have lost a spacer that went on the crank before the pulley ( crank pulley is nearer to engine than water pump pulley) but I don't think it's the case. Could it be that the timing cover is not original, maybe its sticks out further and so the water pump is further out. I'm lost for any other ideas. Can anyone please.

The engine is a 3.5 Rover V8 from a Rover SD1 car.

The issue you have is that the P6 and Buick water pumps are for the very short crank pulley used to have one groove for just the alternator. The P6/Buick was short so the crank pulley would clear the steering rack as installed in the MGBs & P6 Rovers. The SD1 crank pulley is the opposite. They stick out really far in order to fit the alternator, AC and power steering in that order from the front to the rear on the pulley. The steering rack on the SD1 & TR8 was under the front of the oil pan. You can try to space out the Buick pulley to get it aligned with the TR8/SD1 crank pulley on the rear groove and remove the rest of the pulleys. Another route is to get a Buick crank pulley. With all this said and done the next problem is going to be your alternator aligning with the water pump and crank pulley.