Left/Right not working on dual-modded PS3 SE stick?

I’ve had my PS3 SF4 SE stick dual modded for PS2 for a while now. I finally got some buttons to replace the standard Madcatz ones yesterday, but when I went to use it after replacing them, I found that my Left-Right movement no longer works! I’ve checked all my internal connections and they’re exactly how they were before, so I don’t know if the MadCatz PCB went bad, or if the stick PCB went bad. I haven’t had a chance to try it on my PS2 yet (just moved and haven’t dug it out of my boxes yet). Any thoughts? Every other button and Up/Down movement works fine.