Good way to punch scoop holes in hood???

Tape the hood with good quality masking tape in area of cutting no matter what technique you use.

If its me I use a small diameter cutting wheel...like 2-4" max. 1/8" thick and cut the groove shallow first then work your way around.

A plug in Dremel will also work very well if you use the larger diameter
wheels....they are 1.5" or 40mm I believe. Be ready to have several, like 10 or more on hand cause they are fragile.

4" or so hole saw is another way that will work fie if you use a good drill that has good torque....like a 1/2" drive.

Once you cut through paint the edges with something and let them dry so it protects the metal before you install the grommet.

Follow through and have a steady hand and you should be OK.

Mop