71 b body radiator hole ?

Have a 71 SSP originally with 318 and AC auto on column.

If I measure straight across the top of the radiator opening its roughly just over 26 inches.

Is that the largest hole or was there a size bigger for big blocks?

It sound like you car had the factory 26" radiator due to the A/C. There are two sizes used 22" and 26". So you have the largest one that there was.

Thanks for the info I appreciate it.