Hello Jed,
First of all, do NOT drill a hole, it will ruin the device. I looked this up on PocketNow.com and they said it is better to get a holder for the AirTag. Some of these include the [link|https://www.apple.com/shop/product/HNPR2ZM/A/belkin-secure-holder-with-key-ring-for-airtag-black?cid=aos-us-seo-pla|Belkin Secure Holder] for $12.95 or some Apple [link|https://www.bestbuy.com/site/home-security-safety/bluetooth-trackers/pcmcat748301221690.c?id=pcmcat748301221690&qp=brand_facet=Brand~Apple|products] that range in price from $29 to $39. If you do not want to spend that much money there are some cheaper alternatives that you could find with a simple Google search. I hope this helps.
Have a great day,
Evan