k- frame swap

Not sure what you're asking. If it is about putting an Aspen (F body) K-member into an A-body, Red Fish is dead on. No go.

If you're asking about putting the V-8 from the Aspen into the Swinger, that you can do. Schumacher makes a kit that will allow your existing K-member to support the small block V-8. Other options involve swapping out the K-member for one designed to support a V-8. It just depends on your objectives and you budget.