Sounds good, thats assuming the Mustang II does work with the S-10 and doesnt have excessive bump steer? Not trying to rain on your parade as that might be the common swap I am unsure, there are some great books on suspension design out there if you feel uncertain, maybe Tech will chime in as well he even had one where they incourage you to duplicate the geometry on a cardboard model to check it out (sounded cool) Nothing beats driving a well designed car you built that handles well, but the opposite is true if it has issues, I'm sure you know that.
I think you will feel safer without the welding the first time you hit that giant pot hole and wonder if the welds held! Before you cut off the tie rod threads I would run a die down them and make sure it will thread easily before, that way if for some reason it wont you havent ruined a good rack (I bet it will though) Best of Luck