I believe the same points and condenser, and possibly the distributor cap and rotor will interchange with a distributor for a 235. The 426 is the smallest of the "big" GMC engines, with the 503 being the largest one. Ed Pruss has a 1954 630 series truck with a 503 in it. You might want to send him a private message to see what information he might be able to provide. I drove that truck from south Tennessee to the reunion in Kansas city a few years ago after Ed broke down on his way from Cullman Alabama to Denver. Quite a trip! I changed the points partway, and the ones I used were identical to points for a 235. A point gap of .016" and a plug gap of .035" will get you on the road- - - -not sure if that's perfectly accurate, but it's in the ball park.
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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