Well I dug up some casting #s from a couple of respective bellhousings.
SM 465 5-1/8" Dia. (GM5)(3925505)
SM 420 4-9/16" Dia. (GM11)(3815891)
I/I #4101
'71 GMC Jimmy 350, sm465, np205,3.73 posi.
'68 C/10 Stepside 292 (.030 over) Offy Intake, 500 CFM AFB,Clif headers, sm465, 3.73 posi.
'67 K/10 454 project.
'72 K/5 rolling frame project.
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