It's worth a try... I swapped a gen3 trigger bar into my gen4 G17 and it worked perfectly. I tried the same thing (I thought it made the trigger smoother, and it did on the G17, G19 well not so much) and while it worked on one gen4 the other didn't work well at all.
If you are comfortable doing the work yourself, it's worth a try. But be sure to "run it hard" in testing before you rely on it for SD. Let us know how it works out for you.