I had a 69 El Camino. It had a 307 and I swapped it out for a 350. Had a 350 Turbo Hydro Automatic Transmission and it really moved.
One of the best Cars I’ve ever owned and it looked really cool. Black with Dark Gray contrast along the bottom and matching Hood Stripes. Made it look like an SS.
Of course it had Chrome Cragars with big fat tires and everything. The Eight Track worked like a charm. LOL
My dad had a 69 El Camino as well. 350 auto. He’d had it for years, the engine developed a knock, the paint was starting to go, had some rust. But, rather than selling it, he kept it for me to learn to drive in, the deal was no public roads, keep it only on the private gravel road and farm roads around our home. I had a blast in it, I was 14.