Need 57 Chevy Truck Grille Info

[electros]

I am doing a custom grille for a truck but do not have the grille yet- I do not want to buy then tear it apart until I have the correct demensions-the 1957 type-what I need is the meaurement of the open space on the outter chrome ring measuring from the inside from side to side and top to bottom-inside demensions only since I will only use the outter chrome ring-if anyone has this year and could give me the measuremnts it would be grealtly appreciated-the plan is for a 60s style Rat Rod with a 54 toothed type Chvrolet car grille center to fit within this ouuter 57 truck grille ring- thanks
electros@aol.com