My 68 has factory air that I have converted back to R12 and it works pretty good while cruising but at idle it warms up a little too quick and in Florida that's not good.

Has the factory fan clutch which appears to work, I just think I need a little more airflow across the condenser at idle.

Condenser appears to be original but in good shape, I know I can swap it out for a more efficient one but trying not to open the system up again.

Anyone have experience with a bolt on that won't require any major cutting or retrofitting?

There are no seals that I can see between the condenser and radiator, I think that may help too just don't know if there was/is such a thing.

Engine temp is fine.

 

I like to use factory fans
They are more robust and last a while / work well
I currently have 2 old Honda Accord fans on my Boss 302 in front of the radiator
Depending on how much room you have, I have used Chrysler minivan fans and Ford Contour fans
Some factory fans cost a thousand bucks, like one for a Ford Flex, they fail just due to the integrated relay and then they need replacement
They work great on hotrods if you just use a different nonintegrated relay