Author's addendum:  In step 5, when removing the seat base, lift the seat base slightly on either side (from the front), and look under the seat base.  On either side you will see a square metal post with a hole in it.  If you push a flat head screwdriver into the hole of that metal post, it will release the clip that holds the seat down.
 
You saved me hundreds.  Thanks!
 
M corbley: Thanks for letting me know.  It makes me happy to know that it was worth my time to post instructions.