I recently encountered a situation where I needed to change the bulb in a Vivitek D963 (or WD963) projector. I was a little clueless as how to do it and scouring the Internet didn’t turn up any results (or I was just searching poorly).
Anyway, I did finally find this page which explained the process.
I’ve included my own pictures below to help clarify the procedure with real-life images.
Find the screw on the back
Slide the top panel off to reveal the bulb’s location
Unscrew the 3 (in my case) screws as much as you can, then pull the old bulb out using the handle.
Just reverse the steps to get the bulb back in. Extremely straightforward.