Lowering a 72 1/s ton with rear leafs

[muddpile]

Greetings. I recently purchased a 1972 Chevy custom deluxe long box 1/2 ton. It has rear leaf springs and the single solid driveshaft converion. It also has 5 lug wheels, a 350 and an automatic. Like most of these trucks, it has that way too high look to it. I was wondering what it would take to lower it. I have been looking through an LMC Truck catalog, and see that they sell a lower tubular control arm set for $400, 2" front drop springs for $160 and 4" rear drop springs for $170. Is this a good way to lower my truck, and how will it look? It has the factory 15" rally wheels on it right now, but I will likely be going bigger (18-20"). I suppose that shouldn't affect anything, however, because I will go with a lower profile tire to keep the same overall diameter. Is $730 a reasonable price to lower my truck 4" all around, or is there a better value out there with the same results? Does anyone have a picture of a 4" drop?

Also, I've always liked the adjustability of air bags on a vehicle. How much modification would there be and would it be worth the added cost to do it that way instead of the coil springs method.

Basically, the bottom line is that I want a lower truck and will be doing all the work myself with the help of a few friends. The roads around here are not great, so that also has to be taken into account. Thanks!