D100 slant build

since I almost have dads motor finished up, and my car is seeing the light at the end of the tunnel, I want to pull the slant out of my 69 d100 maybe the end of the summer and give it a nice rebuild.

This truck is just a driver that needs to get good mileage and I'll probably pull a trailer with a 4 wheeler or two on it. So I'd like to gear more towards lower rpm torque. I plan to keep the intake, 2 barrel carter, and exhaust manifold. But am open to suggestions. What would be a good cam to throw at this thing? Stock? Or is there a good aftermarket for this application?
If it matters it's a 3 speed manual
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