I use a piece of all thread with 2 large thick flat washers to pull the bushing into the block, if you don't have any assembly lube put gear oil on the outside of the bushing and a little in the block and the bushing will pull right into the block. Don't hit it or try to drive it in, its oilite brass and can easily brake if you try to drive it in and it can also
damage the top and the shaft wont go in or will be tight, I have been doing this way for years and never had to ream one.