I have done those types of reinforcements on my k-frame. Unfortunately its a convoluted pain to put pictures here, on my end at least. If you pm me with your email, I'll send you many photos of what I did on mine. Also this is my build thread on For B Bodies Only which shows some but not all of what I did.
https://www.forbbodiesonly.com/moparforum/threads/updating-the-super-street-mopar.116131/