Driver side air duct drain tube firewall cutout diameter?

[tugger.5000@out]

can anybody measure this cutout diameter in their firewall for the driver side air duct drain pass thru?
Have a new body and only want to drill once. I think 1-3/8”

 

[chrlsful]

dont have the rubber?
Same trouble for a ‘fresh air tube’
on pass side of core support, ’73/4 +.
I need to triangulate the hole B4 I put the
‘grill’ back’n drill an oblong hole (1/2 radii each
end ona rectangle), mount the tube & run it back to the carb hat.

 

[jeffncs]

1.5”