ACS upgrade questions

I started on my upgrade today and it went very smooth. The instructions were clear and complete. But a couple of questions.
On Step 8, my ground wire was yellow, not green. That was the wire attached to the the ground terminal of the power socket and a nut on the inner wall, so I hope that was the right wire to leave.
On steps 19-22, why do we replace the inner fan? The new fan was identical to the old fan. Same brand, model number, label, everything. That was one of the more difficult parts of the upgrade. Was it really necessary if we already had the same fan?
On Step 23, what “sound deadening material”? I don’t see anything. Where is it supposed to go? Do I need to get some “fuzzy Velcro” and put in here somewhere?
Thanks for any help.
Looking forward to my first cook with the ACS Wi Fi controller.
On Step 8, my ground wire was yellow, not green. That was the wire attached to the the ground terminal of the power socket and a nut on the inner wall, so I hope that was the right wire to leave.
On steps 19-22, why do we replace the inner fan? The new fan was identical to the old fan. Same brand, model number, label, everything. That was one of the more difficult parts of the upgrade. Was it really necessary if we already had the same fan?
On Step 23, what “sound deadening material”? I don’t see anything. Where is it supposed to go? Do I need to get some “fuzzy Velcro” and put in here somewhere?
Thanks for any help.
Looking forward to my first cook with the ACS Wi Fi controller.