it sounds as if you have one for a b-body they are just a bit taller. You can use it but will need to modify the lower shield on the core support to do so.
I use the factory tanks and straps and get them re-cored. It costs more to do the bubble top then the square top radiators because of the core design. So I think 69 and up a-body sounds like it would be most cost effective to do. A radiator shop and can change hose outlet sides and widths. An a-body lower is 1.5 inches while the b-body one is 1.75.
i have a 68 barracuda, and an 06 5.7 hemi
the radiator that champion list, says it will be 22.62 tall. that would fit...but the one i got is 1 1/8" taller than spec'd, that don't fit. they don't know why, and don't really seem to care..