[Richard]

Yes, on the leaks on the spud assembly.

I can't tell you which O rings, but I took the whole thing apart including the sliding pieces inside the spool valve and sourced o rings at lowes to replace every O ring. Lubed them with plumbers silicone grease and reassembled.

The two tricks are tightening the two valves to the white plastic plate with the plastic knobs on top, and tightening the two wing nuts that secure the plate to the back of the tank.

I put the assembly in place and barely snugged the knobs, so that the valves would be held onto the plate. I then tightened the wing
nuts to secure the plate. I gently moved the assemble as far forward towards the toilet seat as possible and then tightened the knobs.

If I did the sequence in reverse and tightened the assembly to the plate, and then the plate to the toilet. I would pull the assembly away from the toilet and it would leak.