How strong is the frame?

[72kool]

Ok so in my journey to make my truck my permanent daily, I'm looking into my towing needs. I came across this thread about a 4x4 swap http://67-72chevytrucks.com/vboard/s...d.php?t=659340

My understanding is that the C20 frame is stronger than a k20 frame? Someone posted a lot of specs from a manual and it says the C20 is 32% (I can't remember exact number) stronger than the k20. Is that correct, Or am I reading it wrong??

Reason I'm looking it up is I am looking into a gooseneck hitch, which will be challenging with the coil springs. But first I am looking into the strength of the frame. I see gooseneck and 5th wheels pulled with k20s on here alot but never a C20. Any insight would be appreciated