Truck looks great!
On the shims if you go to Home Depot/Lowes ect where the concrete pier block hardware is, they have hardened steel galvanized square washers that are used for the screw adjusters that are about 1/4" thick, similar to the link here but thicker, the hole is large enough to allow body bolts and possibly the mounts center spacers too..
http://www.homedepot.com/p/Simpson-S...PHDG/100506799
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