103's are pretty tough, as long as it has oil and coolant in it, it oughtta be fine. I wouldn't run it at 70 in 2nd gear for 20 miles but, those are pretty remarkable engines as a rule.
The onlys ones I've seen bad were either run hot or run out of oil.
Project Smoker, '87 603 powered wagon
Hauler, 96 CTD can you say torque?
Toy 73 Cougar xr7 convertible
Acme Automotive Inc.