Welcome to Guitar Tricks, redhed62!
Most guitar cabs were built without being 'designed' for their compatability with the speakers in them. Most of the stacks were simply made to be impressive-looking. I gave one of our members some tips on how to tune a cab Click here. If you click the search icon at the top of the page, and type in "speakers" or "cabs" as the keyword, you'll find lots of info.
Good Luck,
L.