Hello. The seal swap isn't too difficult. You may have to unstack. If the washer is on the bottom, you may be able to scoot the dryer back enough to make the repair, but the washer case is like a cabinet; each part depends on the other parts for rigidity. For this reason alone, it would be much safer without several hundred pounds above your head. I'd unstack. That said: You can certainly diy. Unplug the washer. With the door open, look at the bottom of the seal. You'll see a ring
clamp. Loosen the screw and remove the clamp. Peel the seal inward. It is easier to complete the seal swap with the front off. Remove the door and set aside. Locate the screws for the front of the machine and remove them, gaining access to the seal. Youcan either set the door to the side with the door lock wires still attached, or unclip them, which is easier. With the seal folded inward, you will likely find another clamp at the bottom. Loosen this as well. Remove the seal and replace with the new one, making sure to orient it like the old one was, and fold it to the inside like you had the old one for removal. Replace the front panel. Complete the seal installation, being careful to make sure that the clamp removed earlier gets put back in the groove and seats well. Reinstall the door.
Best Regards, --W/D--