Here's my shock mounting upgrade I did just before heading to MCR last September.
I used 2" square tubing for the main crossover tube and welded 2" square tubing to the ends which are set and welded to the top side of the frame centered over the bumpstop brackets on the frame. 8)
I used the plasma cutter to cut out the opening on the bottom side of the tube and then drilled multiple mounting holes for the shocks in the drill press.
I cleaned up the edges and removed the seam on the inside of the tubing for the shocks to fit inside for mounting.
Here's the shocks in the tubing and you can see where the tubing is welded to the frame.
Here's what the overall install looks like. You can see that the shocks have adjustable mounting points. 8)
NOTE: I have since changed the lower shock mounts since they didn't allow enough up travel. I will add photos of that later.