Hey new guy.. Welcome

For the #4 make sure it's not touching the wiring for the O2.
On your catless pipe, your car might dump fuel if the rear O2 keeps checking to see why the cat isn't functioning.
ZZP plastic spacer shift kit? I'd prefer buying metal spacers at Home Depot or Tractor supply for $3 total.
HUD: that plastic is a real pain... I've done it three times and only one time did it come off w/o breaking. Warm summer day is the trick. Oh.. and a lot of swearing.