Hello I have a 1990 Silverado flatbed, I am looking to put 38" BFG mud terrains on it, my question is, will a 6" lift of any kind fit those tires? I dont care if its tuff country, super lift, sky jacker.. whatever, I am just trying to figure out what lift will put my truck high enough to fit 38's. I am also considering a 2 inch spacer to set the wheels out quite a bit if that helps anything? Also, if i go 8 inches, will i need to lengthen either of my drivelines? and what affect will the high lift, tires, and driveline do to my gearing? I was planning on gearing it down anyway but if anyone knows what size of gears will be best please do tell. any help would be great, thank you!