Options? Buckets were an option. You could get a very bare bones 738 car. My nephew has one that documents as a 396/350 hp 4 speed. It had a 3.55 12 bolt posi, metallic brakes, rear window defogger, AM radio. No tach, no bumper guards, not a single power option.
If you wanted a manual trans, it came with a 3 speed unless you paid extra for a 4 speed. The 3 speed was a heavy duty 3 speed, not the same as if you got a 327/3 speed manual.
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1966 Strato Chief 2 door, 427 4 speed, 45,000 original miles
1966 Grande Parisienne, 396 1 of 23 factory air cars (now converted to a "factory" 4 speed)
I think to answer your question about standard options on a 738... wheel well trim and sd trim was standard as was the 396. I think everything else was an option listed separately on the build sheet. 736 cars had standard buckets and console as well, 738s did not.
I had heard that you couldn't order an SD without hubcaps or other upgrades wheels. But my basic hubcaps were shown as an option code. Only gmvvs could answer if there was an sd with dog dishes, or no radio fir example.
