Mortise lock needed?

A quick learner from Kentucky says:
September 5, 2020
If I buy the keyed sliding door handle set 82-087, can I use my existing mortise lock, which is 3 1/8"? Also, the thumb latch on the photo for 82-087 moves to the right, but my existing thumb latch moves to the left (away from the door frame). Does that matter?
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Casey from SWISCO responded:
September 9, 2020

Hello,

The 82-087 is not handed and can be installed on a door that opens to the left or right. To confirm if the 82-087 would work with your current hardware, we would need to see photos of your handle set and mortise lock. Thank you!
A quick learner from Kentucky says:
September 13, 2020
Actually, my question is not whether the door can open to the left or the right, it is that in a door opening on the right, the same as you picture, the thumb latch shown on your site swings to the right toward the door frame. My existing one swings to the left, away from the door frame. For the other question, here is the photo of the mortise lock.
Thumbnail of the uploaded file named IMG_3982.jpg
Thumbnail of the uploaded file named IMG_3957.jpg
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Casey from SWISCO responded:
September 14, 2020

You should be able to just install the thumb latch facing the opposite direction as long as you can line it up with the 82-218 mortise lock insert, which appears to be a match to your original lock and is compatible with the 82-087. Thank you. 
A quick learner from Kentucky says:
September 20, 2020
Many thanks
Mortise Lock, Round Face, 3-11/16"
Mortise Lock, Round Face, 3-11/16"
82-218
$11.70
Legacy Keyed Handle Set, 3-15/16" (1-1/8" to 2-1/2")
Legacy Keyed Handle Set, 3-15/16" (1-1/8" to 2-1/2")
82-087
$112.27
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