Help Decoding a Small Block

[Chan-man]

I have a 1976 GMC Royal Sierra 1500 Long Bed. It’s more of a Frankenstein truck as it has Chevy door panels and what I believe to be a 78 carb. My issue is I went to replace the carb and a 1976 edelbrock isn’t fitting properly. I’m now wondering if the intake has been swapped or the entire engine. If it has been swapped then what type of engine and what year is actually in my truck. I took a picture of the engine code as best I could tonight and am attaching it but haven’t been able to find the vin on the block yet. Any help is appreciated and will look for any codes I can if I’m told where to look.
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[geezer#99]

Clean that pad off better so we can read it then we can help.
What does a 1976 edelbrock carb look like.
Post a pic of it.

[LT7A]

Originally Posted by Chan-man

I have a 1976 GMC Royal Sierra 1500 Long Bed. It’s more of a Frankenstein truck as it has Chevy door panels and what I believe to be a 78 carb. My issue is I went to replace the carb and a 1976 edelbrock isn’t fitting properly. I’m now wondering if the intake has been swapped or the entire engine. If it has been swapped then what type of engine and what year is actually in my truck. I took a picture of the engine code as best I could tonight and am attaching it but haven’t been able to find the vin on the block yet. Any help is appreciated and will look for any codes I can if I’m told where to look.
Posted via Mobile Device

Since you are speaking of original equipment, do you mean 1976 quadrajet? Are you working toward originality, or trying to get the correct equipment for emissions? Searching online for Chevy small block casting numbers could help you start being able to decipher what is stamped into your block. As geezer said, hard to read it in the picture with the old paint and oil. Wire brush maybe?

[Just call me Sean]

Posting the picture upside down doesn't help either.

[Getter-Done]

Flip for ya.
As mentioned, if you clean the paint off,
One of us could probably help you.
When you get the info, I would spray-paint the pad again to keep it from rusting.

[44th Miss Inf]

If the engine code is FCN, its an ‘84 305 4bbl, 160hp that had a manual trans from a pickup

Definitely a 77 or later block as it has the narrow pad