Pull the right side cover, remove the clutch basket, remove the crankshaft primary drive gear on the crankshaft. This will give you access to the seal. Now, drill holes in the seal and install sheet metal screws. Use pliers on the screws to pull the seal out. It may take quite a bit of effort. Make sure no filings got near the bearing. Installation is the reverse. Make sure to grease the seal so it doesn't burn up on the initial start. Try to set the seal at a different depth in the hole so it doesn't line up with the old wear grooves on the sleeve. Otherwise, the crankshaft sleeve is replaceable. Also, it would be wise to order a new washer for under the nut that retains the clutch, the one with the bendy tabs on it.
I am not going to check that bunch of jury rigg'in!Crank seals do not just up and go out for no reason.Chances are good your crankcase bearing is going out.The depth you set the seal at is crucial,to deep will block the oil passage.Safe is usually to the bottom of the chamfer and is good reference for having the seal square.