I had good results using Universal Super 68s with Scott-Matthauser pads - but I used different levers with them. My memory is that the late, much missed Sheldon Brown had written somewhere about mechanical leverage of different brake levers and how Universal's design wasn't good, but I may be misremembering things or conflating things he wrote with someone else.
If it was me, I'd consider swapping out the levers and using good cables with lined housings.
Russ Fitzgerald
Greenwood, SC, USA