Is there a certain way to remove the back panel. With the washer standing upright, things weren't going very well.

I actually just did this. It's a total mess. Very cheap washer not made to be accessible for repair. There are a ton of screws and shank clips to remove from the back. It's not going to look pretty any way you do it and reassembly is twice as hard. Start with some kind of flat, stiff, preferably plastic pry tool like a putty knife (plastic so you don't scratch the paint) and slip it under the front right corner of the control panel and pry it open. It may be tough- don't be afraid to hulk up. Do the same for the left side. From there it should be pretty self-explanatory. If you are doing anything with the pump, be very careful. The pump is a cheap piece of plastic that will crack if you so much as sneeze on it. This thing shouldn't even be on the market. If it's not accessible for the owner, the company is trying to screw you into paying for service.