Paul,
Welcome to Stovebolt.com.
There is no 3600 model GMC ("52 GMC 3600").
You might be referring to a GMC 150 series (3/4 ton truck)?
There is a GMC 102 series 1/2 ton longbed (same size bed in a 150 series GMC and in a 3600 Chevrolet).
What 6-cylinder engines are you referring to?
GMC (228, 248, 270, 302) or Chevrolet engines (216, 235, 261) - you might want to designate make and cubic inches.
Last edited by tclederman; 04/21/2017 2:38 PM. Reason: correct 228 typo error - thanks showkey
