Nice looking project man, I gotta come over inperson an check it out. Let me know if you need anything! 

Was that 43 bucks brand new? How much more arch do those have than the stock Dodge ones?FULLSIZE said:the GM rears are 63" long and are way more common than the late model dodge springs. paid $43 for the pair.
if your goin outside the frame, i would go with the half ton springs(4 leaf + the overload). this should work good, but the secret to getting good(useable) flex is the shackle length. a longer shackle will let the spring grow and shrink as it goes through droop and compression. if you use a rear spring front hanger in the rear(shackle flipped) and build a long shackle, i think you'd like it.Are the 1/2 tons and 3/4 tons the same? I want alot of flex, I am going with a 3/4 Elliptic setup in the rear. Do yours compress well, meanning not real stiff? I know some 1/2tons have 6leaves for the HD setup. Guess I would want to stay away from those. Mine are going outside the frame rails. Thanks for the info!