Slot 2 DS mod

[xpertguitarist13]

I was thinking about how the DS does not play the old gameboy games, so my question is, would it be possible to take the cartridge slot out of an SP or regular gameboy advanced and put it into a DS so it can run all kinds of games? I know that I could use an emulator on some sort of homebrew device, but where's the fun in that? Any help would be appreciated, Thanks!

[Aricado]

It can't be done because the ds has only the gba processor or wtf is called so it can only play gba games in slot 2. You can tell that if you look at a gba,gba's have a small switch that is pressed when you insert a non gba cartridge and switches to the gbc "wtf" thing (gbc mode),that also explains the different design of the cartidges.
So in few words the answer is It can't be done.
I was searching for that some years ago and found a site explaining how to do it and the process to do it was so long,complicated and sounded effective. I didn't take the time to do it as I was reading the comments below which were like "I'm gonna sue you!!" "You motherf*!@*g scum" and similar stuff :P
So I took my time instead to find why it can't be done and yes I did it!!
If you want to see it with your own eyes take a gba with no cartidge inserted and press that switch on the right side when you turn it on and gbc mode will operate.
  Thanks for your time reading this. 
David aka Aricado.

[xpertguitarist13]

Thanks! Yeah, I did look and that was the case. Too bad really. They should have made it completely compatible.