I am going to be putting lowering shakles on my truck. Is there any other modifications I need to to? Any bed mods? Do I have to take out the overload?
By putting on drop shackles, the pinion is tilted forward by a few more degrees. In some instances too much pinion angle can cause problems with traction, drive shaft bind, proper lubrication of the rear end, ect...
I don't think there is really anything you can do to the front hangers sort of torching them off and welding them back on in a new spot. The other option is to cut the spring perches off and weld them back on at the stock angle.
The third and most popular options is to put the drop shackles on and enjoy the new stance of your truck without anything else done. Many, many people run drop shackles alone on these trucks without any issue at all. You can just put them on and be done with it. To get a few more inches lower, you could take out the overload.
http://www.4wheelparts.com/parts/manufacturer-productlisting.aspx?ptID=5502&mid=SKY&subCat=64
http://www.summitracing.com/parts/RAN-RS8125?autofilter=1&part=RAN-RS8125&N=700+115&autoview=sku
Something like these but I think steel is preferable.
Any offroad shop or leaf spring supply place would have them.
Y do I have to remove the hitch?