Can you post a picture of the solenoid? There are two basic types of solenoids for Delco starters- - - -one that attaches to the starter field housing with four bolts, and one that is attached to the nose cone with two bolts. The plunger that engages the starter drive is the same, or at least similar on both. Oldsmobile, Cadillac, and automatic transmission equipped Chevy 6 cylinder engines used the 4 bolt solenoid in most applications. Rock Auto used to have a listing for those solenoids. Do you need a 6 or 12 volt item? The 12V solenoid can be used on a 6V starter to avoid violent engagement of the starter pinion and possible flywheel damage on voltage-converted vehicles.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
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