High torque 360 LA build camshaft recommendations

A friend wants me to build a 360 La for his Ram truck. It is a work truck always loaded and pulling a loaded trailer. He is interested in as much torque as possible.
Years ago I put together a 350 SBC with the early small valve " power pack' (triangle on the front of the head) heads. With a small Sig Erson cam. It pulled very strongly but was all done at 5000 rpm.
I have a set of 67 273 heads and was thinking of putting them on the 360.
Cams have changed over years, what would you recommend for a cam ?
Mid 70's 360 la probably around 8:1 compression
Stock tranny and converter
3.54 axle
About 28 tires
Stock single exhaust with catalytic conv
Thermoquad on factory iron intake


Just my two cents but the engine you want for your described application is a 5.9 magnum with an upgraded cam. Best bucks down approach.