Tubular Lower Control Arm Thread

Aside from it being overbuilt from the factory because it is designed to take the suspension loads, and triangulating a bracket to put the inner end of the control arm in double shear, there is no reason to screw with the K frame at all.
Being that all the work is going to be in strengthening the engine box and longitudinals for the upper shock mounts, building those mounts, making everything hell for stout (because you're now jacking all the corner weight into the top of the engine box instead of the middle of the chassis through the floor shear plane), and coming up with tubular upper arms to allow shock clearance, why not just weld boxing plates to the bottoms of late B body lower control arms (78 Cordoba, etc.)?
BINGO! Tubular lower control arms with a flat upper surface to mount shocks to and a shape that naturally provides more suspension travel. You just need to use longer upper arms to match their slightly longer length and machine an insert in place of the T bar to take a bolt through the newly added bracket mentioned above. Wacking off the control arm pin and drilling and tapping it to take a mounting bolt should be child's play after that.
No worries about suspension geometry, because it remains all stock!