'Goodfellas' Actor Mad Over AMC Trigger Warning

AMC is getting a "Sicilian message" of sorts from one of the "Goodfellas" crew after the network slapped a new warning on the mob classic ... causing fans to flip more than Tommy -- aka Joe Pesci -- being told to get his shine box.

Here's the deal ... TMZ recently reported AMC added a warning over outdated stereotypes in addition to violence and language ... and, it caused some serious online backlash.

Frank Sivero, who played the hilarious stone-cold killer Frankie Carbone, tells TMZ the trigger warning is not just unnecessary ... it is an insult to the actors, who include Robert De Niro and the late Ray Liotta.

Sivero -- who was born in Sicily --  says there was nothing stereotypical about his mob character, who is heavily featured in the movie until his classic demise in the back of the meat truck.

As he tells TMZ, director Martin Scorsese had the actors improv a lot of moments in the film, especially after a murder went down, so the choices were their own ... not an exaggeration in need of a trigger warning.

The Oscar-winning flick is a beloved classic, Sivero notes ... so by now, people should know what they are getting into when they fire it up. They don’t need a warning, especially an insulting one.