Robert,
I like your thinking. Everyone is rushing towards the MII conversions or ifs front clips when straight axles can be made to run straight, ride good, handle, and turn easy for a fraction of the cost. Dragsters are running well over 300mph now and they ALL have straight axles; not much "wander" there. My wife's fishing truck is a 1964 Ford which was the last year for the straight axle before they went to the #!&*% twin I-Beam set up. I rebuilt/replaced every single part that could wear and then installed caster wedges to give a six or seven degree increase over factory which makes it go arrow straight down the road but increases steering effort a bunch. A Toyota p/s box is the cats meow for straight axles trucks so in it went along with a p/b booster and polypropylene strips between the spring leaves (teflon is too soft, thicker, and tears up easily). A sway bar and good shocks wrapped it up and gave a driver as good as the newer trucks. Since it is used a bunch off road the ride height stayed the same as I was afraid to lower the back because all the fish she is going to catch might bottom it out.