DD, who owns FREIGHTLINER?
I'd imagine you could have what you want.
On the other hand, seeing the number of dissatisfied O/O's with EGR engines I'd rather have a glider kit and a re-man N-14, early 3406E or similar. The 12L Detroit is popular in those discussions. The one I drove last year (recent in-frame) got outstanding mileage.
Some good reading out there on this subject; see
Fitzgerald Truck Parts & Sales
Came across one guy who dove deeply into spec'ng one for himself. He said the order was sixteen closely-spaced-line pages long.
A lot of these guys are dead serious about FE, but know that the money (at this point) is in a reliable engine itself tuned for best economy for what they do (given optimal gears, transmission, tires, etc). An O/O has different perspectives on FE than a fleet, but even SCHNEIDER is said to have ordered 900 glider kits.
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