I think I,d drain and flush out the cooling system and change the oils in the starting engine and the diesel to start with before I ran it. Also check all the other oil levels and grease the rollers and idlers.The hyd. oil tank is in the front of the radiator if it has that tank on it and it has a cap to check the oil.I don think it would hurt to use some real fine emery cloth to lightly sand the rust off the ram but don,t go too hard on it. Don,t forget to remove the diesel block drain plug behind the area of the inj. housing lower in the block so you get all the old coolant drained from it and then flush it out with the plug out.I believe they have a 3/4" hex head on the plug if I remember correctly.
Either real fine emery cloth or crocus cloth should polish that ram up. The main thing to look for is if the chrome is flaking off and to get rough edges off it otherwise it'll tear up the seal.
SJ has it right . .check all oil and coolant levels and change as needed. The last thing you'll want is for the cooling system to rust up or crack the block if it freezes.