Yes the radiator swap isn't too hard. Be careful with the plastic radiator shroud. It is held-in with two metal clips. Use a pair of plyers and pull gently straight up.
A lot of radiator shops rebuild MBZ radiators. I got mine done for about $150 several years ago.
Additionally, becareful of the plastic outlets/inlets and the little elbow that goes to the overflow tank. These tend to get quite brittle with age.
If one breaks try repairing with JBWeld. You have to let it sit but it saved me from having to get a whole new radiator just recently.
MBZ coolant can be purchased from this site. Give'em a try. Great people.
'03 E320 Wagon-Sold
'95 E320 Wagon-Went to Ex
'93 190E 2.6-Wrecked
'91 300E-Went to Ex
'65 911 Coupe (#302580)