Fix what's wrong, not anticipated failure
The original post was misread by several of us, but if you reread it, the problem is a deteriorating upper radiator hose not his radiator neck. There is no need to change out the radiator if it has no signs of leakage and no apparent stress cracks.
"Tell me and I will listen, Teach me and I will learn, Show me and I will accomplish, Involve me and I will succeed."
'84 300SD 256,000 Gold on Brown (Mileage Award)
'86 300E 246,000 Blue on Tan