oil pump driveshaft

I usually do the same as Moper only difference is I use a complete shaft with the gear still attatched (only if the cams is out though) put some thick grease on the shaft just under the head of the drive gear slip the bush onto the shaft and use the drive as a guide and drive the bush into the block.
The drive makes sure the bush goes in straight and doesn't **** over and go egg shaped which is the cause of most of the problems.