Cooling a big block

[Musclecar]

I have the shroud installed with the clutch fan.. No luck... Will the Mark VIII fans fit without much fabrication?

[ProdigyCustoms]

We have following Shroud / fan packages in various sizes. They are designed to fit our radiator line. but we also used one on the 69 Firbird griffen as Kevin already owned the Griffen before we took on the Northern line.

I just need the measurement between the tanks and top to bottom of the core will it will mount.