K frame modification ?

I don't see why you couldn't. You could add a skid plate as a reinforcement anyway, I add them to all of my K's when I seam weld them.

Here's the '68-72
IMG_3465.jpeg
this is a '73-76
s-l1600.jpg

s-l1600 (1).jpg

Here's a Firm Feel skid plate added.
KFA3.jpg

Or you could add one more like the factory piece
skidplate.jpg