[OMR]

You must drill the extra 2 vacuum ports to really note a major change.
You just have to be careful and take your time. After you pilot a 1/16 drill, look from the back side for alignment. If not centered, just reinstall the 1/16 drill and side drill to the best location. Now with best location, drill with a 1/8.

If you totally goofed up, buy some JB Weld and plug hole. Let dry 1 day and then start again.

Jetting, for winter, 180-185 DJ main, summer a 175. This with stock CDI and endcap.
Pilot screw out 3 turns winter and 2 1/2 summer. This with 40-45 jet and stock cdi.

OMR