I am not sure they will help, but Trijicon's "custom shop" is ToolTech Gunsight. The web site is
http://tooltechgunsight.com/ and the phone number is 248/628-1811. The email address is
sales@tooltechgunsight.com
I believe the modification, if possible, will need to be done with steel sights, as the plastic Glock uses is not very strong. I suspect the plastic sight, with a tritium vial, would quickly fail under recoil due to the extra mass of the vial acting as a lever. The Glock plastic sights are also known for eroding just from holstering, further suggesting the plastic sights are not a good host for tritium vials.