OK, 2 schools of thought from the factory.
GMC trucks that had a V8 from the factory had engine close to the radiator. No fan shroud was used. The bellhousing crossmember was also located 4 inches forward of a chevy crossmember, or even a six cylinder crossmember.
Chevy trucks with the 8 used the same rear crossmember as the six cylinder trucks. This caused the V8 to sit to far back to effectively pull air through the radiator. A fan shroud was used to overcome the distance.
My 59 gmc had the factory pontiac based v8. I don't believe pics of my engine bay will help much, as My engine is mounted like the stock GMC V8, with a cushion mount under the front timing cover, and the two bellhousing mounts in the rear.
