After running to a craft store to get some more adhesive vinyl, I cut the rest of the stencils. After applying them to the mugs I re-used the pieces of contact paper I applied them with to protect more of the glass.
After applying the etching cream and leaving it sit, I washed the glasses and removed the stickers.
These turned out great! even the details in the letters (which are not shown in the pic)
Why didn’t I get a cutting machine a long time ago?