Didn't use a guide, it's a bog-standard Arcade1Up conversion. A couple years ago I looked up a display driver board providing an HDMI input to the stock display and bought a $50 Amazon-sourced EG STARTS-brand cheapo kit of sticks and buttons with USB encoders. They were drop-in replacements for the stock deck's buttons and sticks. The emulator driver right now is just a 6th-gen i5 HP EliteDesk Mini fleet-salvaged workstation booting into RetroArch.

These days you can go even easier with fully installed plug-and-play Arcade1Up control panel replacements that are literally drop-in - MDF, sticks, buttons, encoders, and audio/display driver card are all built in. You just pull the stock control deck out, drop the $150 Intec deck in, and connect whatever PC/console/FPGA into the video in and USB controller outputs that it provides. You can build a cab around one out of plywood or just grab a random Arcade1Up on sale somewhere.