Never ever drill holes if you don't have to. And luckily with the Z32, you don't have to

The hole below exists, and is covered by a rubber plug.
From the inside, you remove the door sill plastic trim, kick panel trim, and you can access the hole. I believe it's a 1.25" OD x0.75" ID grommet I used. You could goop it with silicone if you felt better about it, but the fender liner covers all that.