Is replacing a cracked upper screen worth the effort?

I've tried once before when I was younger to replace a screen on the classic 3ds xl, but I broke a number of pieces along the way. Now I am much more competent with building machines and repairing them but this device scares me. I already bought an “oem" part and I wish to at least practice. Does anybody have enough experience to tell me what to look for and should I hold off til I can use a lower risk /broken/ ds to practice on?