Awesome!  Thank you for your replies.

Katsumbhong, just to clarify I am talking about faint horizontal lines that appear rather than the darker areas at the edge of the screen.  If screen pressure does cause random lines to appear then I stand corrected.

Unfortunately that guy is the only one around with a white backlight in stock so I went with him.  Yeah it's a tight fit alright.

ShintarouMusi, Thank you for easing my mind.  I think you may be right that the lcd is just old.  I'm just really really glad that it's virtually impossible to see them with normal contrast during gameplay.  It must have been some ocd kicking in and worried the screen would mess up more.

So I'm itching to mod another Gameboy and just happened to acquire one very cheaply.  I bought an ASM backlight this time to see how this one goes.

That happens when pressure is pushing against the LCD screen.

The Handheld Hero BLs are a real tight fit.

My boys do it too, I don't think it's anything to worry about. I think it's something that just happens when LCDs age. ¯\_(ツ)_/¯

Finally got home and took a picture.  Here's what I'm talking about.  Does this happen to everyone else?  They're not noticeable making the contrast darker and normal.  You can see them more towards the bottom to the right of the plant.

PS, When I get home I'll try to take a picture and see if they'll show up.  They're very very faint and horizontal.

One way you can see them is to play Pokemon, walk into a house, go to the very left or right sides, and play with the contrast.  When lighter the lines will appear.

You can see them more easily on darker pixels made lighter in contrast.

Hey chipmusic forum, I'm hoping you guys could help me out on a problem I'm having with my Gameboy DMG.  I couldn't find any other place to get a public input.  I figured since everyone here is very knowledgeable on the subject I would get the best help.

So anyway, I just recently did the backlight biversion mod on my old Gameboy with the kit and inversion chip on this site, http://www.handheldlegend.com/.(sorry if they may be a competitor, I have no clue who's associated with who).  I made sure to be extra careful with everything and it worked out beautifully.  I put in the white backlight and inverting the display twice made it so much better.

Recently I've noticed that when I'm playing a game that if I play with the contrast and make it lighter I can see horizontal very very faint dark lines.  When playing a game you really don't notice it one bit unless you try your hardest to see them.  I figured out that these lines are caused by powering on and off the system.  You usually see 1 bright line across the screen.  This also would happen without ever modding the handheld on everyones.  It seems like in this case it's burning it into the screen?

So my biggest question is that if this is a normal occurrence and if I shouldn't worry?  Do I have screen and power issues?  I did everything by the book correctly.  I noticed this morning that a lot of the lines from last night disappeared, but some still remained.  Wondering if the screen just needs some rest to disappear.

BTW, I'm also playing one of those Chinese bootleg multi carts with all the Pokemon games on it.  Any thoughts if that is somehow affecting the situation?

Thank you in advance for your help.  It is much appreciated.