Changing Hydro fluid on a B9200 hst

[bvshearz]

New to the site, looking for a little help.I've owned this B9200 for about 10 years and have NEVER changed the Hydro fluid.I've changed the filter every year and added a quart of fluid.Not having any problems,however after talking with the local dealer he's suggesting that I change the fluid.I have NO owners manual or service manual.I'd like to know from someone who's changed it their self just how hard it is.Only one drain plug in the tranny?Does the same fluid also run the PTO or does it have a separate plug/reservoir?How much hydro fluid do I need? 5 gallons?Any advice would be welcome,Thanks.
Bob
Independence, Ky.