One would think that just getting a decent frame, fully refurbished and in excellent shape, that I'd be happy to slip it under the Rover and carry on. But no, not me. I've got to fiddle with it!
What I'm trying to accomplish is a further modest lift of about 1 - 1.5 inches. The easiest way to do this is to extend the spring shackles at the back of both front and rear springs, but to get an inch, I've got to add 2 inches of shackle length, and an inch and a half requires a 3 inch shackle, which starts messing up the castor geometry on the front end. So, since the frame is bare, I thought, why not increase the height of the fixed spring hangers at the front of both front and rear springs by an inch or so, and then I can increase shackle length by the same amount to get the desired lift. And, the added bonus of not jiggering the steering geometry. This is essentially how the military 109 1 ton is set up, so I figured it should work for me.
Starting with the front... The photos show the spring mount for the front of a (rather rusty) military 109, turned upside down to compare it with the spring mount on the stock 88 frame, pictured above.
After a little bit of testing for size, basically by taking a new bushing with me to the steel shop, I concluded that 3" square tube, 1/8th" wall would be a good starting point as it accomodates the bushing, albeit tightly. 
The drawback is that 1/8th wall is a little thin for my purposes, as the stock measures to 5/32" and I am intending to lengthen the mount, thus it will be subject to increased leverage from the springs. The military mount is 3/16" thick. I can't copy the military mount precisely without alot of fabricating as it is an entire unit that mounts to the frame horn. Instead, I intend to cut the mounts off of the existing frame and adapt my new mount on the resultant flat square surface. 1/8th being too thin, but fitting the bushing well, I plan on using another 1/8th flat steel left and right to give it rigidity and mount it to the original mounting.
The military mount appears to be set back from a stock 88" mount by about 1.5". I'm not sure whether the rear (of the front) spring bushing is moved back accordingly, but I'm hoping to keep my hole placement about .75" further back, rather 1.5" further back. (I'm thinking here that .75" won't affect things much with an extended shackle at the other end)
So, a couple of days ago, I proceeded to get out the angle grinder, attach a cutting blade and cut off the existing spring mounts from the left front. No turning back, now. I then cut a length of 3" tubing with about a 10° angle so that it would follow the profile of the mount as it comes from the frame. Not knowing yet exactly how tall I intended, I left a long enough length of tube. I also intended to leave at least an inch of the tube intact at the rear in order to maintain the inherent rigidity of the square tubing.
(After completing the first one, I've decided that this rigidity is even more important and I'm not even cutting the open side out until I finish welding the reinforcements in place. Due to the heat of welding, the first one ended up warping inward by about 1/16th" and I could no longer insert the bushing until I did a fair bit of hammering and bending on it in the vise — but I'm getting ahead of myself a bit!)
As can be seen in the photo, I've scribed the positions of the new spring hanger hole and the rounded shape I anticipate for the top. The other thing to note when doing this is that the original spring plates are positioned towards the outside of the frame, with the inside edge sitting approximately even with the outside edge of the frame below. By positioning the 3" tube flush to the outside I am within about 1/8th" of the original side to side placement, and have a lip of aproximately 5/16th" to deal with on the inward side of the frame. This will be apparent when you see the photos of the reinforcements.
After reading the green bible I couldn't find much documentation on precisely why the spring mounts were positioned outwards and not centred. An alignment issue? Anyway, thought I better follow the original pretty closely.
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