57 with 390

I greatly appreciate the response but no one has answered my key questions!!!--do the "C" mounts face with the "open" end of the "C" toward the firewall or toward the front of the car as this would make about a 1" difference in how far forward or rearward the motor sits.-Another way to look at it is to measure from back of block to the firewall--this distance will tell me if the mounts are on backwards or correctly--my suspiscion is I have them backward but before I lift motor again and change I would like to verify--thanks .Does anyone know for sure if the engine-side bracket for the Z-bar is different from 57 to a 63???