Lowering 69 GMC

[EddieB383]

I have a 1969 GMC swb truck. It's got leaf springs in the rear, drum brakes all the way around. The front drums will be replaced with discs, and more than likely the rear will be too. I would also like to be running 18 or 20 inch wheels all the way around. That being said, I'm looking for lowering information. Ive read numerous threads with seemingly contradicting information, so I figured Id post my own. I need to know how much drop I can get out of the truck without notching frames, or doing much (if any) cutting and re-welding. Rough price estimates of parts would be nice too.