Originally Posted by nathanD.rector
If I had to replace a radiator,I'd go with a custom alulinum one,with 4 rows.
HELL YEAH!! With an emphasis on the "hell yeah."
Look at any hot rod magazine, such as Hot Rod Magazine, and at the back, you'll see a ton of folks who do such a thing for a living. Total cores = wallet weight loss ability, but you can have these things built, rebuilt, customized, etc for pretty reasonable amounts.
And if (purists beware) you're ok with a non-Mercedes radiator, there are tons of radiators from tons of V-8 engines born in the US, Germany, England, the Far east, etc that cool as effectively as a 60s or 70s era radiator.
For my own $$, I'd go with total custom, all aluminum, maximum cores. And I'd change the thermostat too, whether or not the thing had it coming.