Terry,
I am in the process of installing a Ford 8.8 under my 1999 XJ. If you know someone who can do the welding for you it is not a bad project. You can get spring perches from a stealership for about $10 a pair. The guy that is doing my welding said he could quickly make the shock mounts from scraps, or you can use the ones from your old axle.
Most of the expense (aside from the axle purchace) has been doing the brakes. I bought my axle from a salvage yard. It had been sitting on the ground so the rotors and pads were completely shot. Plus the emergency brake shoes had completely locked up. And they cut the brake hose when they pulled the axle. Fortunately explorer brake parts are cheap but still, rotors, pads, e-brake shoes, and left side brake hose. It adds up.
You might also be able to get the u-bolt to pinion flange if you ask for it. Try to if you can, it will save you $40.
-Brian
BTW: As an outside observer I saw nothing in VintageSpeed's responses that was out of line or deserving of being flamed. Tone is tough to read, I get in trouble with that all of the time. I recommend you relax and assume everyone is trying to help. Making the tread look like a personal battle or flame war will only keep people from posting what you do want to hear.