Remodded the case based on Koji's suggestion, but may have found the bigger problem trying to fix the wrong thing.  I got a chance to play around with where pressure on the ribbon caused my display to mess up, and think it may be due to some ribbon damage I hadn't noticed before likely caused by me not being careful enough when trying to fit the modded display into an improperly modded and therefore too small of a case.  Below I have a picture of the screen display without any pressure to the ribbon:

Since this looks perfectly fine, I never assumed I had damaged components of the screen.  The next is a picture of the screen with pressure on the ribbon attached to the bottom of the screen, caused by reassembling the case:

The double-image seen here is only present when putting pressure on the right side of the ribbon at the bottom of the screen, which led me to noticing damage to the ribbon itself:

I recognize I'm pretty far off-topic from the K-B front light mod being discussed here, but I figure it's a problem that some of you guys installing the mod may have run into.  I guess I'm really not sure where to go from here, but I've got to assume that my screen problems are from the damage seen in the last photo, right?

Koji-Kendo wrote:

Thank you. Here's one that's also very good: http://handheldlegend.com/pages/instructions

I have run into your problem early on. Perhaps this tutorial of mine can help elleviate your situation.: http://imgur.com/a/EyElT#9
Particularly the "cutting and trimming the inside of the front shell" portion.

If you need more info, I have a sub-reddit with lots more tuorials, guides and stuff.: https://www.reddit.com/r/Koji_Kendo

Also, the Game Boy sub-reddit community is really good and can help you if my solutions cannot.: https://www.reddit.com/r/gameboy

Hope that helps!

I might love the people of the chip community even more than the music.  Thanks for being so helpful - I looked up the newer trimming you linked to on imgur previously, but hadn't realized the older trimming had similar problems when you did it.  I'll start there; the extra casing isn't doing anything positive so it can only stand to help.  Also it looks like the only easy fix on hand... I'm novice enough that I'm still worried about breaking things too far to keep fixing.  I'll be happy if at the end I accomplish all the basic mods I'd like and still have a working unit.

I'll be sure to update with the results in case others run into the same problem.

Koji, great mod instructions.  I followed along and successful installed my frontlight bonded to the CGB screen.  Physically, I've encountered a weird problem I cannot seem to solve though.

The ribbon to the bottom of the screen is bending too much when I try to reassemble my gameboy, and leads to the screen image messing up.  I followed the tutorial by removing the foam behind the screen for extra room, but now the ribbon is just pressing directly against circuit board.  Has anyone had this problem?  How can I prevent the ribbon from bending this much?