There is plenty of information on the web about Spal dimensions. Go to
https://www.spalusa.com/ and you'll get dimensions, CFM, side view PDF's with dimensions, amperage draws, etc.
I’m referring to dimensions of the aftermarket traditional fan shroud for the mechanical fan.
**Update**
I found a vendor on EvilBay that was smart enough to list the dimensions in the item description. It doesn’t say where the centerline of the cutout is at the bottom for the radiator outlet but it looks pretty close. Hooray, I might spend some money here soon.
Fan Shroud Measurements: Height: 18" Width: 27" Fan Opening: 19-3/4" Depth: 8-1/2"
LINK TO SHROUD ON EVILBAY. 
