39 chev dash to floor measurement

Does anyone know what the distance is between the lower dashboard and the body mount area on the floor of a 39 chevy sedan? My lower cowl and floor pan is rusted out and I'm planning on replacing the bad panels but I need to take the sag out of it.
Thanks in advance.

 

I have a 39 chevy 2dr sedan in the shop right now.I measured 21" from floor to bottom of the dash. It is a finished car so the carpet and pad is probably 1/2 to 3/4 of an inch also.

 

my sedan measures 22 1/4" from the floor to bottom of dash right next to the door hinge post.

 

Thanks!
You guys are awesome!