You probably are on the right track for using the original radiator. The leading edge of the fan needs to be inside the fan shroud for the system to work properly. If the truck came from the factory with a V8 the radiator was designed and mounted correctly for a V8. If the truck came with a I-6 the radiator is entirely different. Aftermarket 3-4 row aluminum radiators are fairly cheap and you can get them truck/engine specific. Good luck.
Martin
'62 Chevy C-10 Stepside Shortbed (Restomod in progress)
'47 Chevy 3100 5 Window (long term project)
‘65 Chevy Biscayne (Emily)
‘39 Dodge Business Coupe (Clarence)
“I fought the law and the law won" now I are a retired one!
Support those brave men/women who stand the "Thin Blue Line"! Hug a cop!
USAF 1965-1969 Weather Observation Tech (I got paid to look at the clouds)
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