I did weld up my D50. Although, like many, I have always hated the IFS suspension, it was not my invention/idea to weld it solid. I Got my ideas from Swamp donkey's page, and from Huff who also did it.
My welding, although usually very solid, isn't usually very pretty. I pulled the whole thing from the truck first, lined it all up on the shop floor, paying attention to spacing of the springs, and accepting that castor/camber shims can be used to fine tune/align things later. I opted to cut off the passenger hinge point, and left the one on the drivers side, and then used 3/8" buttress plates and 1/4" thick angle iron to join the 2 halves. I spent about an hour aligning it all up before I finally started to stitch it together, and then I had it inspected/aligned by a well respected front end shop locally, and it drives straight as an arrow.
I used springs off a crewcab F350 with 460 gas, and it handles much better than before, but the ride is a bit bouncy. I also used all the steering stuff off the F350, because the stuff off the IFS axle allowed quite a bit of "bump steer" and it bucked horribly when turning sharp in a parking lot. I've had a new set of tires on there since last summer, and I can't even see a hint of wear.
I'd do it again in a heartbeat, my only complaint is that it took me so long to get up the nerve to do it in the first place...
..from the front..
..from above and behind..
(Told you the welding was ugly!!)
..from below and in front..
Lastly, I want to add a bit about the reverse shackle. This pic describes it:
So, Just to be clear, the Reverse shackle only works on positive arch springs. If you put one on a negative arch spring, it actually makes the ride/handling worse!
Just my .02...