While @ the steel yard, I also picked up some 4.5" OD steel pipe needed to complete some new rear bag mounting 'hats'.
The rear suspension was originally set up w/OE truck arms & shop built 2" lowering blocks which put the bag @ the exact installed height needed. I've since swapped some Porterbuilt 3" drop TA's which altered my height requirements. My c-notch is the limiting factor on ride height so even w/the 3" dropped TA's vs. the OE TA's w/2" block, I don't get any more drop. The PB TA's do allow me to use the 'hats' for mounting the bag which means no drilling a bunch of holes in the frame. I can also adjust the exact height of the hat so the bag travel & compression is optimal (which I did
).
Instead of the upper stud being centered in the mounting plate/hat, it will be off-set which allows me to use the existing OE coil-spring mounting holes even though the rear is not @ the OE dimensions. In the last pic, the OE upper hole location is just inside of the leading edge of the round tube....