My Osram bulb arrived and I followed the fairly simple and obvious steps in this video BULB REPLACEMENT FOR WD-65738 WD-65838 WD-73738, WD-73838
Don't touch your new bulb. You will need gloves, and a magnetic screwdriver. Securing that wire at the end is tight. Unplug your TV and don't remove the old bulb until it's been off for at least an hour.
It only took about 10 minutes and was easy, except in my case, in the very first step, both of the plastic tabs snapped off when I tried to pry the assembly open. The good news is that the cover snapped back together anyway and it feels pretty tight, despite having those little pieces broken off. I would be very surprised if it created any problem.
The Osram bulb appears to be identical the the OEM bulb that it replaced, and was half the price of a whole assembly, so I'm a fan so far. It fired up and is definitely brighter than the old one. Will put it through it's paces in the weeks ahead.
For what it's worth, I spotted this Guide for spotting counterfeit projection lamps
, but only after I installed the bulb, and I'm not taking it apart again just to check. If anybody else orders, it would be interesting to run it through this checklist.