Very nice build! Looking forward to see where it goes from here. I'm also considering picking up a 1st gen tundra to build.
As for the 6112's, I run them on my 4th gen 4runner and find them to be as close to a rebuildable coilover as you can get. I'm pretty happy with them so far. That being said, I run them on the 4th notch (early 6112 with only 5 notches) and a spacer on the driver side, which is just about perfect for a mostly stock 4th gen with 2" Icon springs in the rear. However, I'm building a steel full plate bumper for the front with a steel cable warn winch and I already know it's going to be too much for the 600 lb springs that come with the 6112's. I already have a set of King 14" 700 lb coils to try out.
Keep the pics coming!