Another 273 question

Just my .02. I would look at magnum manifolds for the exhaust instead of headers. On the four barrel, I’d just have the top of the manifold opened up and use a four barrel adapter with a 500 cfm or less of carb. Or maybe even a much reviled Eedelbrock street master, SP2P, or Offenhauser dual port redrilled for the bolt hole angle difference. On the cam, talk to Ken at Oregon cam grinders, and get something in the range of a “Dump Truck Cam”.
But then, gut instinct takes over.
I can understand wanting to keep the car’s original drivetrain, especially since it has good oil pressure and compression. And if you’re like the majority of us, you’re budget is your ultimate limit on feasibility. But that’s a fairly heavy car for a 273. And then there’s the mention of towing. It’s almost an empirical law of science that anyone who tows with a given vehicle will eventually find themselves towing and hauling more than they originally planned. The best parts from with the same plan for the 273 (early crank converter hub and full floating rods, closed chamber heads) applied to a 318 block with some 1.76ish compression height eBay cast pistons and small bore NOS head gaskets just makes more sense to me (along with a factory iron four barrel intake or equivalent). Cubic inches and cylinder pressure for the win. I feel strongly enough about it that if you were willing to go that route and closer I’d give you a bare block (flat tappet or hydraulic roller) and a streetmaster intake (needs the water temp vacuum switch hole hole welded) just because I’m tired of tripping over them, and would rather see someone who needs it use it instead of it being scrapped.