This kit engine carries the Ford Diesel valve covers. I believe that the Ford LNT carries the CAT 3208, not sure. The engines are identical in both kits with the exception of the badging.
CAT OTR engines in kit form, 3208, 3406, 3408. The 3406 is an inline six and is a generation model in 1:1 meaning it started as a 3406 to a 3406E. These have since been replaced with the C-series engines. The kit form you will see in Revell Pete snap kits is a 3406. The other two are V8's and also no longer in 1:1 production.
I had not planned to plumb the tanks, but now I might. You will need 2 lines from each tank. . 1 from the bottom of the tanks to the fuel filter. 1 return line from the injection pump to the top of the tanks.