We have two set ups, one boat with Ullman pods and one boat that has a shelf mount which is simply the seat mounted onto a custom stainless mount. Both setups are bolted on and removeable. If you don't have access to the underside of your deck Ullman sells an insert made by Zodiac which works great.
If you PM us or send an email to email@example.com
with your email address we'll get you some pictures.