Is there a holy grail thread for shortening lwb to swb frame

[rs74]

I have read a few different post about shortening a lwb to swb frame. I think I have seen three different ways to cut the frame. Pretty much I would be cutting out 14" out of the middle right behind the cab. What I have seen differ is on the back of the frame. I have seen cut 3" and also seen cut 6". Which? Also what is the best design to cut the frame and splice back together. I have seen just making 45 degree angle cuts and splicing back that way.

I have also seen what I call the half nazi swatstika type. Then there is the swatstika type and then cut out a diamond shape within that and weld it back in place. Kind of hard to describe. Just looking for the best design or way to cut and splice back together. Also do I need to weld in a glove or inner support plates.