I don't think I saw this thread until today. DSE's first and second-gen clips both take the first gen crossmember. We found this out when we picked up the phone and called them after a customer was having a fitment issue.
Today, we offer solutions for the 67-69 and 70-73 F-Body and the 68-74 X-Body. Direct-fit transmission crossmembers are available for Turbo 350, Turbo 400, Powerglide, 700R4, 200-4R, 4L60, 4L65E, Muncie 4-speed, Richmond 5- or 6-speed, and many Tremec 5- or 6-speed transmissions.
Crossmembers are 1-1/4 x .120"-wall steel, dual-tube, fully enclosed structures that are stronger than OEM stamped designs and rigid enough for the vehicle to benefit from stiff polyurethane transmission mounts. Tubes are mandrel bent to provide 3" dual-exhaust clearance and to correctly position the mount for each model transmission.
Note: Installation on factory or DSE subframe requires additional adapter kit.
More Details Here:
http://www.cachassisworks.com/c-157-...irect-fit.aspx