I looked them up at Ames.
It looks like they have at least one hole for a mounting screw on one side I cannot see the other side.
Do you still have the original ones installed?
To make plastic more flexible you could soak them in some hot water if they need to snap over the seat belt retractor.
I am not exactly sure what obstacle that has you worried, yet if they are a tight fit for some reason a little heat works wonders.
FYI to post pictures.
Save any picture you want to post, to a place in your computer where you know where to find them.
When your typing a post on your PC click on Go Advanced under the cell where you type your post.
This will give you more advanced options for writing your post, one of those options look like a paper clip, click on the paper clip.
This will open a pop up window with 5 cells that read Choose File.
Click on the top cell ( choose File ) and this will direct you to search for your saved picture.
Find the picture you saved then click on upload, wait for a few seconds then you will see a link to the picture appear in the same pop up window that was opened earlier for you.
Repeat the process four more times for 4 other pictures if you choose to do so.
If you only need one picture then just close the pop up window.
Click on preview post to make sure the picture you wanted to upload is present, if all is well then click on submit.
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