Pistol trigger guard question

[Noeyebrows]

I have a Ketland trade pistol kit from MBS and I was wondering how the grip portion of the trigger guard should be secured. All of the antique originals have no screws or pins visible. I assume that leaves filing a beveled spur on the end of the grip portion of the guard and undercut the inlet likewise to secure it under the wood. Let me know if I am way off base if anyone has some input on how this was done on originals. Looks like the front of the guard is pinned in the usual fashion.

 

[Comfortably_Numb]

A hook and nail was often used.

 

[Sam squanch]

I believe there was a lug on the back strap that would hook on a small wood screw in the grip strap inlet. I read a high quality pistol trigger guard should have no visible means of support. Much like me 30 years ago……