Route your PicoBoot connections to the Serial Port 1 bay, and mount your Pico to this adapter to plug into the Serial Port 1. Easy access and no tape/glue required. Uses 4 M2*6 screws and M2 nuts (M2.5 should work as well).
I printed this on a resin printer for accuracy.
Note: the creator of PicoBoot recommends you don't install it in the Serial Port 1 bay, due to wire length and potential future upgrades that involve the Serial Port 1. Some in the modding community may think you're making a poor decision. Just remember: it's your console, do what you want.
The author hasn't provided the model origin yet.