Finally found way to get up there..... I found that Sheet metal screws might not work.... The metal seems too thick. But the holes are the same type that the metal side panels use for their #8 truss screws.... Just un taped .... And They look like there sized for a #6 .... but the head of a #6 might be too small for the vent flange. When I get a vent, I'll know. Im guessing they drilled all the holes to fasten the sheet metal at the same size.... And to use the same type of screws... A #8 truss head machine screw. Why would they use a #8 machine screw for the interior sheet metal and just 4 holes for the vents using a #6". And why change from a truss head screw to a panhead sheet metal screw for the vent?
Inquiring minds want to know....
Mike
