I had an horrible incident here - https://www.clublexus.com/forums/is-2nd-gen-2006-2013/925356-how-do-you-remove-rear-rotor-lexus-is350.html
My front driver side window was shattered.

I saw a glass replacement on ebay for $90. Removing the door panel should be easy but how do you replace window glass? Is there a tutorial for this?

 

you have to lower your window to a spot where u can see 2 10mm bolts in the 2 holes which is near the bottom of the door, then u can stick a socket in and then un-bolt whatever is left.. then make sure when u put in the new glass that it is on the guide, if not then it's not gonna work lol... then just bolt it back up and test it...

 

Just open up the door panel the rest is very self explanatory. You won't be confused on what to do

 

I've never done this car but on every other car I've had to dismount the window guide from the inner door frame to allow the glass to be inserted.
I recall one vehicle being designed so poorly you had to pull the weather strip out, insert the glass into the guide and then fight the weather strip past the window and use instant adhesive to glue the material back together. It was miserable!

If the glass won't just drop in, follow the guide to the doors bottom and unbolt the guide or loosen it. Put it back where it was when done.

 

I changed the glass myself twice on the 2nd IS cuz insurance won't pay for Lexus glass and gives me aftermarket crap, don't need to remove guide, just interior panel off, plastic weather seal off and roll down window until u can see the 2 10mm bolts, unbolt it, lift one side up so it can slide out...