I have a 4 inch drop axel from Sid's in OK. I found that with 15 inch wheels the axel is the lowest point, not real good if you have a flat. After doing some figuring, if I use 17 inch wheels everything will clear. My only issue is that I wanted to run 15 inch raised white letter (RWL) tires, no one make a RWL in 17 inch. I have a set of pristine 15 inch Corvette Rallys. So I'm still looking at wheels... Nice Chrome .
Like tuts, I also did the 4” dropped axle with 15” rims. If I blow a tire my axle is 1/2 off the road. If the tire comes off the rim, my axle will become a plow. My front axle is roughly 4.5” off of the pavement. Double check your scrub line to ensure that you are good. PM me if you want pictures!
Chris