[indivi]

What about upper parts, like putting a Gen 4 EDP + spring and extractor in a Gen 5 G19 or the G45.

I've successfully put my G45's firing controls (trigger, housing/spring) in my G19.4 and have around 250 rounds without an issue through it, but I've often wondered about the upper. The EDP looks to be the same, but the Gen 5 spring is noticeably a bit longer.

 

[indivi]

The upper parts are different between the Gen 4 and Gen 5 for the most part. Gen 5 uses a different firing pin, extractor, safety plunger, and slide cover.

The following parts work with both:
firing pin spring
spring cups
firing pin channel liner
spring loaded bearing (LCI only 2714)

I cross referenced all parts using the Glock official parts order from dated 11/5/2020

That was pretty much the same info I had, I was just curious if anyone had tried it.