2007 Hummer H3 fuel door replacement

[collega]

Hello, everybody!
I decided to replace fuel door on my 2007 H3. Original fuel door is badly damaged by winter road salt long time ago so I bought AMI billet style brushed aluminium lockable new fuel door from e-bay particularly for 2007 Hummer H3. They said that it's very easy to change it and to install new one without drilling holes. I try to find any videos showing how to replace it for Hummer H3 but all videos just about any other kind of trucks wich have different from Hummer H3 installation process steps.
Is anybody have any idea how to do it? Or may be somebody did it already for his H3? And I don't know how to remove original old fuel door because all screws and fixtures are badly damaged by salt. 
Any suggestions, please?
Thank You.

[ChadB]

Mine is all messed up as well.  Last summer I attempted to clean it up a bit and repaint it body color.  However it is again messed up due to the winter harshness.  I'm dealing with idle issues so it's become lower on my "to do" list but I'm looking for ideas as well.

[collega]

I bought for replacement after market fuel door from e-bay. In comparison to original OEM GM Hummer fuel door new one has keys and could be locked plus it's brushed aluminium Billet Fuel Door so it should work different way( I hope!). So installatuon of it is also different from original GM OEM one.