Impressive work.
Word of caution about the rear sling connection point on the SureShot stock. I have one and so does my friend on our 870 Supermags and both broke. I honestly do not know how I broke mine I went to shoulder my 870 and the bottom sling swivel simply popped out. Thankfully I didn't drop it.
I used a marine grade stainless steel shoulder eye lift bolt to install a new connection point for my sling swivel and it worked great.