this was posted by Ingeniero No1 a while back.
I have tried different size drill bits, and have settled on No. 48 (0.0760), but 5/64 (0.0781) works well also - for 16 AWG stranded wire and the No. 0 screw; that is.
After I drill the hole and insert the No. 16 AWG stranded wire (26 strands of No. 30AWG), I use a pick to separate the strands to make it easier to start the screw.
From Micro Fasteners. I tried different head configurations (button head socket, slotted, and phillips pan head) and these worked best for me:
Product No. SMPPK0004
Pan Head Sheet Metal Screw - Phillips
Size: #0 x 1/4
Finish: Black oxide
Price: 100 for$ 4.30