I have the 2.5" BB kit and am really happy so far with my 1/2" longer synergy fixed hd arms. Very easy to install, easy on the bank and really made a difference above 60 mph.

 

What about fixed lowers on the rear?

 

I first used Warrior Products fixed front lower and rear lowers suitable for 3" lift. They really did work great for correcting pinion/caster, but the rear arms are atleast 1.5" shorter than stock to correct the pinion. With that, it drastically shortened my wheel base. Also using standard poly bushings, allowed for the same amount of flex stress on the mounts as oe rubber bushing arms. Much nicer/safer using arms with flex joints now.

 

If you're only going to replace 1 set on the rear, do the uppers first. That'll help correct the pinion angle without losing anything off your wheelbase.

 

Wheelbase is okay. If did do them, I would buy adj/uppers immediately along with spring wedges for they would rotate the pinion down beyond the current 7degrees.