I have a 2000 Z28 with SLP Loudmouth and SLP Y-pipe, how hard would it be to install a cutout? I really wanna do this

 

why? your LM is basically a cutout that's open all the time. only difference is it dumps out the back of the car instead of under the rear passenger seat like a cutout does...

 

It's super easy. Just take the cutout to a muffler shop and they will weld it in for you. For the electric plate, it's very fun to install. Get some write-ups and you will be fine. I haven't done it but can imagine what it's like.