I am looking at a 50's metal fendered Kenworth as my next project. It will be mostly a restoration but I may take some liberties with powerplant and drivetrain to make it more fun to drive. The truck I am looking at is what they call a "low mount" It has a little shorter radiator and cab. They were commonly used as fire trucks along with other stuff. Current motor is an ailing 220 Cummins. I have 3 primary options I am looking at and then a couple outlying ones I would consider. #1 if I can find a healthy one would be an NHRS 300 Cummins supercharged engine. It is era correct, they sound awesome and would be all the power that truck would need. They are hard to find and also hard to obtain parts for anymore. 2nd/3rd Option would be move up to an 855 based motor like a 335 or 350 small cam or my bread and butter, a Big Cam III 400. The issues I see are fit and having enough radiator to keep a bigger motor cool. I doubt the truck will ever pull all that much. A car trailer or my RV trailer are most likely the only kind of work it might do. I would consider a Cat or Detroit based on fit and cooling limitations. An 8V71T would probably be sort of a tight fit. I am open to suggestions and ideas. I haven't bought the truck yet so I am only in the planning stages at this point.