I had a bushing just pressed in without the tool on a B engine. I had the engine apart for another reason and found a near miss on the bushing. It was loose in the block and almost spinning and tight on the distributor drive shaft. The shaft was scored. I got a new shaft and new bushing and installed it with the correct tool. Some people have gotten lucky but I would never do a bushing again without it. The bushing was designed to be pressed in place and burnished to size with the tool.