The problem will not be the cooling capacity, which might be adequate. The original radiator will only be rated for approximately 4 to possibly 7 PSI of pressure, and the 350 functions best at around 15-18 PSI. V8's with thin wall castings in the cylinder wall area have a tendency to spike temperatures and produce pressure surges that might cause the radiator to burst even if the complete system does not overheat.

I would recommend getting a modern reproduction radiator with a proper pressure rating that will bolt into the original mounting points on the vehicle. It can also be specified to include a transmission cooler. They are not terribly expensive, but I'm not sure what the shipping cost would be to Europe.
Jerry


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