I'd definitely use Calvert's mono springs.

The Assassin bars offer more adjustability and are a simpler install. Less clearance issues if you have the inboard spring kit.

Calvert Racing is an awesome company to deal with though.
I have Cal-Tracs...bought them long before the Assassin bars came out.


CHIP
'70 hemicuda, 575" Hemi, 727, Dana 60
'69 road runner, 440-6, 18 spline 4 speed, Dana 60
'71 Demon, 340, low gear 904, 8.75
'73 Chrysler New Yorker, 440, 727, 8.75
'90 Chevy 454SS Silverado, 476" BBC, TH400, 14 bolt
'06 GMC 2500HD LBZ Duramax