This is all great advice and will be followed. I am on Steel Soldiers and have found it very helpful, though a lot of folks obsessed with "bobbing" trucks. My Dodge M37 is also very slow up hills, the one to Detling showground almost killed me...
One area that was very rusty (well non existent in places) was the windshield surround, the bit that folds out. I ordered a pair from here on Monday evening this week and it arrived yesterday!!!
http://www.eriksmilitarysurplus.com/
I have it booked in for a full brake service, filters, oil etc and will get the fuel tank checked as well. Rex Ward is sorting this work via some of his contacts. Can't think of a more helpful person!