Retrofitting traction control from a 300b into a 300a is rather easy since the system is handled entirely within the abs module and all the harnesses are present within the 300a. Even the dashboard has the light ready to go.

Parts you need from the 300b:
Master cylinder
Abs valve body
Abs module (Which is on the valve body)
The short trim piece from the dash which has the traction control switch.
The 2 brake lines that go from the master cylinder to the valve body.

Swap all that in and you are done. Remember to bleed your brakes!

I've seen this information in bits and pieces here and there. I just wanted to gather it and confirm that this works for anyone else who happens to stumble on this post looking for information.

Thanks to the guys at crownvic.net