I cannot comment on the Kings Bay area. However we had to have our radiator replaced about two years ago.
It was just as we started on our first trip, and only five hours from home on a two month trip out West.
My RV is on the Spartan MM chassis, 2000, side radiator.
They had to disassemble a lot of the rear chassis area to get at the radiator, All the coolers on that side had to be removed.
I do not think any cutting or welding was involved, although I was told it could happen on some RV's
We also had a fan blade air shipped in from Spartan in Michigan, as mine had lots of cracks all over.
The radiator was going to be super expensive if shipped in from Spartan --- so they found a VOLVO TRUCK radiator which had identical mounts/inlets/exits/thickness-etc.
Saved a lot of money, I think the Volvo radiator ran about $1000, As it was I think the repairs were still about $1700 of parts (including hoses and antifreeze) and $1500 of labor to have it replaced. Not cheap.
This was done at a Freightliner place that also worked on all makes North of Ocala Florida.
Good luck with yours. Dale