I have a 69 with multileafs and still run traction bars. Always have except one trip to the track when I had removed them thinking that maybe I didn't need them anymore. When straight home and put them back on before I took it out again.

I would say add the second bar first and then it you need more make sure your shocks are in good shape and then do springs if you still feel you need them.

All depends on how you drive it.