The Skyjacker 7" kit is going to be in the $3000 range, and is wild!
Frankly, if you're not going off-road, why 8" of lift?
Is this a late-model or a pre-1993 model ram?
8" of lift on a late-model is going to be work, and money, and more work, and more money...
Is it a 1500 or a 2500? I assume if you're going to be going to 8" of lift, you want to run some very large tires. Well, if you go much or 35, I doubt the front Dana 44 will handle it, and you'll have axle reliability problems. So add in another $2000-4000 or more for new axles.
Mainly, you'll need to worry about the driveline angles. Definitley need custom axle-shafts, and you'll want to conver the t-case to a fixed-yoke output, and use a real slip-shaft drive-shaft. You may need to get custom u-joints and yokes made that will operate at the extreme angle it's going to be at.
Good luck, and hope things workout, either finding the size lift you need, or if you fab it yourself, that it works out well.