need link and help for ruu 2.3.5 on desire s

[hillyboy]

Hi all, please bare with me on this, but I am new here and not up to date with all the rooting etc but I own a htc desire s that was running standard on 2.3.5. I was having wifi, Bluetooth and battery problems so updated the rom to 3.6 ics through htc dev site, and the phone was ok for about a month( battery only) and now it wont hold a charge for long. I then replaced the battery but after about a wk the phone started to drain power fast again, so have factory reset it etc but still no change. I would like to be able to downgrade the software back to 2.3.5 but cant find a ruu/rom link to be able to do it. The phone is not rooted and is "s" on.........is it possible to fix it or not? Thanks for taking time to help us out.