1060781
i wouldn't go for anything longer than 2" extension (which will render a 1" lift) because shackles are known to flex if they get too long...
yes, you only replace the shackles that move (front on front axle, rear on rear axle)...
it'll probably be more worthwhile to head to a parts store and buy shackles... they're pretty cheap. (~$40/set) i wouldn't mess around with rising a weld that goes bad if you DIY...[addsig]