Sorry, work's been busy.
I didn't completely remove the XS32's drive (it wasn't bad), I just set the LG on top. If I were you, I'd connect the LG to the power/IDE cables and set it securely on top to make sure it works, BEFORE physically switching drives.
My DVD drive is set as a master, make sure your LG is jumpered the same way as your existing drive before connecting it.
A couple of ribbon cables are taped to the top of the drive; no problem pulling off the tape. The drive power cable goes from the board to the DVD drive to the HDD. Be careful when removing the DVD power connector, as a shielded flexible cable goes into the pc board right behind the power connector. The DVD drive IDE cable ends in a small pc board that plugs into the drive's connector. Gently remove it without bending or tweaking it side-to-side. I don't remember if it's keyed, so make note of the orientation. I'd suggest removing the cables before the drive. Be extra careful with the proprietary cables that can't easily be replaced!
The existing drive is a standard size drive, so the LG should fit perfectly. I'm just not sure how the drive fits into the front panel area, but after looking at it, I figured worst case I could remove the XS32's door. It may not be aesthetic, but it should work. The drive mounting bracket is secured to the chassis by four accessible screws, so it's probably easiest to remove the bracket and drive, then remove the bracket once they're out of the unit. That way you won't have to remove the HDD. My unit also has a clear plastic strip running from front to back on the right side of the drive, so you'll have to remove two drive to bracket screws on that side.
To test the LG without removing the other drive, you'll have to either disconnect the power cable from the HDD and DVD drive, or the flexible shielded cable to get the power cable around the shielded cable to the LG. You'll also have to untape the IDE cable from the existing drive. Don't forget to double check all connections before plugging the unit in.
I'd be curious to know the ROM version and date on the LG when you get it. And the existing HDD info, if you'd like to share.
I'll leave the cover off my XS32 for now, and if you give a heads up on when you are going to try it, I'll keep checking the forum, in case I can help.