I wondered that also. Maybe one is the front axle and one is the rear? They have different option codes maybe someone can decipher them. Here's a better picture of the SPID.
Unfortunately the 327 is gone. It has a newer 350 in it.
Here's a better picture of the carburetor also. I'm not very knowledgeable on them so IDK what it would have come out of. I also found it interesting that it has a HEI distributor. I didn't think there was enough room to fit them in a 4X4 truck.
