Thompson rear carrier identifacation?

Hey guys, i came upon a vintage thompson (mickey thompson) carrier, im trying to identify it, i believe it to be 55-64 gm but im not sure, its got ap219 cast into it if that halps any, tomorrow i was going to dig out a rearend and do some measuring.

anyone have an idea?

thanks
jeff

 

You are correct the #219 is the early GM (Chevy) slug

 

thanks for the info.

 

I know this is an old post, but what would the cost of one of these be

 

I think those are magnesium. A buddy put one in an old dragster.

 

Yer I believe that it is magnesium, I was waiting to no what one would be worth