Hot take: I started using a 3/4 inch spacer block for drawer slide installs and it cut my time in half.
I was getting tired of measuring and marking each cabinet for undermount slides, so I grabbed a scrap piece of 3/4 plywood from a job in Tacoma last week. I just hold it against the cabinet side, set the slide on top, and screw it in, and it lines up perfect every time. Does anyone else use a jig or trick like this, or do you think it's better to measure each one?