AI Short Forend Bridge for AT-X and 20MOA Accessory Rail Kit do not match?

[Glassaholic]

For aesthetic purposes I prefer the short forend bridge and was intending to use that with my Thermal; however, AI made the short forend bridge with only 8 key slot holes and the 20 MOA accessory rail which co-aligns with the 20 moa picatinny action rail needs 9 slots??? Why on earth didn't AI make the short forend bridge with 9 keys??? My options are to use it anyway and only have two bolt lockup and slight overhang or use a non-standard rail that is not 20 moa... what would you do?

Below is the image showing the slight overhang of the accessory rail over the back of the bridge, I could have a 'smith drill and thread a hole in the back of the bridge but should I really be doing that?

 

[Glassaholic]

Here is the top view, you can see there is no key slot for the back hole on the far right.

Here is a standard rail