Here is a quick guide for how I engrave these oil cruets:
Here is the glass cruet I use: Choice 8.5 oz. Oil and Vinegar Cruet with Pourer
I use dish soap instead of masking (easier clean up and I don’t have to deal with residue). Here is a video of how I apply the dish soap. I do not add any water or anything to the soap.
The bottle is just barely under the 2" requirement. Because of this and that I use dish soap, I do not use auto for material height. Here are the setting I use and some tips for adjusting them: