There's a little release/latch on the left side of the guard. I got the the latch release off once but I cannot remember how to disengage it now. However, I still had a problem taking the guard totally off.
So.....
What I did to remove the lamp was take a slender needle nose or (suture clamp) and grab hold of the lamp and slowly wiggle/yank down. Was a lot easier then messing with the latch/guard ...........
I replaced the lamp the same way.
The lamp is hardened glass; be careful to not break it. Putting something sticky on the needle nose helps.
After many attempts to remove this ''Sword from the stone blub''. I used a rubber band to grip around the bulb while applying tweezers. Hope this helps someone. I removed the bulb and ordered a new led one.