Originally Posted by Gramp's59
The distributor for the more common 235 engine won't fit.

Is the problem actually with the distributor, or the vacuum advance unit? I have a couple of 270s with distributors, and a 228. I'll do a comparison and see if I can figure out if there's any way to adapt a Chevy unit to the GMC engine. What kind of problem does your current distributor have? They're very easy to rebuild.

https://www.ebay.com/itm/334851727496? This one's missing a drive gear.

https://www.ebay.com/itm/364236930089? A little more complete.

Once you make a couple more posts and get past "moderated" status, post a few pictures of what you have now, including the part number and serial number. Good luck!
Jerry

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