Great mod while keeping all the SGB features intact
For Super GameBoy Clock Mod
The install was really simple due to the contacts on the board being aligned with the ones on the Super Gameboy. I heard how replacing the crystal could break some features of the SGB, but this mod did none of that! It works like it was described, and the music's pitch sounds identical to the original DMG now. Now I can play Pokémon Gold and Link's Awakening on my CRT without clock speed anomalies.
I also got a link port to put in, since the clock speed apparently is the only thing that breaks link cables. The port is a bit more challenging to install, but the included ribbon cable helped a lot. Shipping took a little while, but since it was just after Christmas the delays were understandable.
Overall it is a great mod with or without the link port, I would highly recommend it to any SGB owners looking to do speedruns or who are driven mad by the music's higher pitch. :)