[OG68]

I noticed all that too but wrote it off as modifications done over the years. They seller did mention that engine was rebuilt at one time but if the existing engine is proof of that, they left some parts off. A quick check of the VIN on the block and checking the exhaust manifolds would settle that question. And IIRC all 68 V8s had the ported vacuum switch. The automatics didn't have the de-acceleration vacuum valve mounted on the passenger rear intake manifold.
I also noticed the headliner hanging down and the cracked dash, split seat covers. Mine looked like that too after spending Summertimes in the Sacramento Valley. But I'd gladly do interior work as opposed to rust repairs.