Stabilizing a rocking Toto Vespin

I've recently replaced a 20yr. old Norris toilet with a Toto Vespin (big improvement) on a tile floor and now have a little rocking as the Toto bowl is secured at the back instead nearer the middle directly over the flange. Would plumber's putty work as a shim/caulk material? Is there a better choice? Thanks to any and all for suggestions.

shimming the Vespin



With Unifit equipped toilets, I shim at the back, making sure the front of the bowl is in contact with the floor.
You may need to loosen the back bolts before the shims are placed.
When the bowl is stable, then you can tighten down the bolts.

The front of the bowl can then be caulked.
You don't want these bowls to rock back and forth.

Plumbers putty is not used for shimming.

Thanks for the "how to". What do you recommend as a shimming material? What comes to mind are door shims but is there something else that you or anybody else would recommend as a better option?
Thanks again.

They sell plastic shims for this. The plastic is also probably easier to cut off so that it doesn't show without splitting like a wood one might. The door shims are probably not a great idea. I think I 've seen them at HD, but a plumbing supply house should have them for sure.