Just a little update.
I went out to my car at lunch and looked carefully at the bushings I bought today.
they are energy suspension for '73-79 Ford truck leaf springs. The nice thing about these is that they are quite long ~2.75" which gives lots of room to adjust the width of my trailing arm end, if needed.
The tubing they will be inserted into is 1.5" DOM with a 3/16" wall. The tubing ID is 1-5/8. Perfect for the bushings.
The bushings fit into the tubing well without the inner sleeve. With the inner sleeve inserted the bushings are a *perfect* fit for the tubing. Very tight.
What I'm doing is drilling a 1-1/5" hole in a piece of 2x2 1/4" wall square tubing. I'lll inset a piece of round tubing into the hole and weld it to the Square tubing. The bushings are inserted in the round tubing. Over all, my lower trailing arms have cost a grand total of $55 including a 1-1/2" hole saw.
A little plug for suicidedoors.com: I payed $40 for a set of 8 bushings and 4 sleeves (enough to do 4 trailing arm ends). The D.O.M. tubing cost me about $6 for the amount I'm going to need. Suicidedoors sells the bushings w/ the tubing pre-cut for $9/end. A bit cheaper than it is costing me to make them myself... However, I had to get a different size sleeve than suicidedoors offers. Of course, I have the satisfaction of saying that I built my own trailing arms... not sure what that's worth.