This is a thing that stumbled on me by accident. My niece was playing her ds lite, and I was fiddling around my GBA(adding X and Y buttons) and I thought - a little rewiring, dremel and It'd fit. So I ordered a DS lite (white) case from DX and am waiting for it, as soon as It comes in the mail, I'll post pics. I plan to add a frontlight from the GBASP (already have 1) and the X and Y buttons will be a combination of (select + L/R). The speaker will be rewired on the left side (with holes drilled) and start select rewired on the right side. Also I plan on using the GBA SP battery. Any thoughts on this?
Here's a quick mockup done in mspaint:
Here's a quick mockup done in mspaint: