Hey Ken, The 322 was not available in 58/59 trucks, it only was available in the 10800 School Bus Chassis.
Also, the 348 was optional in the 1958/59 7000 Series LCF and standard in the 9000 LCF and 10,000 Series Trucks making this a rare thing to see today. The front motor mount "U" bracket for the 348 trucks was unique to them only (cars were different). Group 0.029 p/n 3739937.
I agree, a 348/409 will drop right in anywhere a sbc fits other than fabing the mounts.
I don't know the exact year, but trucks didn't use the "side motor mounts" until after 1959...cars started using them in 1958.
Mike B
