Alignment? That's a big one for me, too. No one has actually been able to state the indexing of the notch from the keyway. It would be valuable information to check balancers with.
Can't remember who that was, but they didn't ask first... I have a generic puller; had to buy new, longer HT bolts (UNC) for the job. Crack the bolt first, then use the puller maintaining about 1/8" clearance under the bolt head as you go. This is fiddly in the car - the radiator may interfere.
Smear the crank nose or balancer inner with anti-sieze. Use Royal Purple or some other lube on the balancer outer as you reinstall, and turn the engine 30-40 revs before starting, to spread the lube over the seal running surface.
The bolt goes back into the crank clean and free of sealant or heavy oil.
The 250 likely runs a larger damper; ours do. It will foul the water pump housing or pulley on smaller motors. As to three and four bolt versions of the small damper, the only constraint should be what, if any, accessory pulleys you intend to bolt up.
Over here, we have rebuilt versions that run a urethane medium in place of the rubber; it's supposed to be much tougher unit and makes it more of a one-piece, supplementary flywheel. The twin groove units are extremely rare to us.
Regards, Adam.
