I have a Federal-Mogul shop specification manual that will provide part numbers and dimensions for rod, main, and cam bearings, piston pin bushings, etc. and dimensions once you get deeper into the rebuild. If you can send me a private message with a mailing address I'll be glad to send you some photocopies of the applicable pages of that manual. I've also got AERA machine shop specification manuals that show connecting rod reconditioning specs, etc. Most GMC's run gun-drilled connecting rods that supply pressurized oil to the piston pin bushings. They're MUCH more rebuild-friendly than Chevy engines.
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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