There is a way to machine the back of the engine block to take a full circle lip seal that works much better than the 2 piece seal. Most auto machine shops have the equipment to do that job, if they know how to set things up. I'd be glad to consult with your machinist if he would want to discuss the procedure. The seal I use is a National #417210- - - -3 7/8" inside diameter and 4 3/4" OD. There are usually several available on Ebay at pretty reasonable prices. Good luck!
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
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