It's just a guess on the cost, most of us probably have this hardware already. While researching how to install my banjo axle seals I came across some info online saying there was a special tool with a long shaft you could buy to drive them home from the wide end of the housing. While I started poking around my shop looking for a way to replicate this I came up with this idea. Rather than bang them in from the inside why don't I draw them in from the outside. This is what I came up with. For all that I know this is an already known method but if not here goes. I took a 5/8 bolt, 2 washers and a nut and slipped one washer on the bolt. I then wrapped some painters tape around the bolt to mimic the I.D. of the seal. This helps to position the seal and keep it concentric to the bolt shaft. Then I lubed up the tape with some bearing grease, slipped on the seal and lubed up the seal O.D. also. With my axle housing fixed in a vice I slid this assembly into the axle shaft and fished out the threaded end on the opposite side. I then added the second washer and nut and spun it down flush to the axle end. Tightening the nut I could slowly begin feeling the seal draw into the pilot, you can feel when it finds home when the wrench comes to a dead stop. Sure beats buying a fancy tool that would hardly get used. Besides I think it is a better method as opposed to beating on the seal. Thanks for reading! Stay safe.