Hi Russ ,
I recently fitted the Ctek ring terminal leads to my Yaris and had to lift the seat base to gain access to the battery terminals. It lifts with a very firm 'yank' and I thought I was going to break something when doing it but it was all good.
I also had to remove part of the insulation from the positive terminal in order to get to the battery post , this is like a Chinese puzzle but is easy enough after a little head scratching.
I then carefully undid each battery terminal and slipped the ring terminal under the nut and tightened it back up.
Take great care when doing the positive terminal not to short it out with the spanner though.
Then fiddle the plastic insulation piece back over the positive terminal , from memory I had to remove a small piece of it with a Stanley knife so it fit nicely with the ring terminal in place.
I then cut a 46mm hole in the black plastic seat base trim to allow access to the charging plug without dismantling the seat to use the charger and purchased a black silicone rubber bung from ebay to fill this hole when not in use.
I hope this helps....