Fair warning to anyone thinking about shimming for the first time … this should only be done if your saddles are bottoming out and your action is still way above your acceptable level, in my opinion.
Shimming when shimming isn’t necessary can cause other issues … too much of a back angle, difficult setups, saddles that are way too high that mess with intonation and tone and even the need for pickup height readjustment, depending on how much of a difference was made after installing the shim.
The right shim placed in the right way and followed by a good setup should leave you with saddles that are still low without having to do a ton to get it where you need it to be.
Just remember - a shim affects all strings. I’ve also had luck sanding some meat off a g string saddle when I was really only having a problem with that one string and the rest were fine. Saved me from taking the neck off and adding a affecting the whole bass.
Just wanted to throw that out there for anyone new to the process.
YMMV, buyer beware and all the other fine print.