VIN and Engine Code confusion

I keep getting different information on some of this engine/VIN decoding stuff, and it's getting confusing.
Basically, I want to verify that:

1. My 71 is a real GS (43437 says it is)
2. It has the original engine (serial code on block matches the VIN).
3. What does the engine code mean? I read somewhere that this code means it had a 2bbl?
4. Why doesn't the Serial Number on the body tag not match the VIN?

Any help will be greatly appreciated and help me sleep at night.

VIN: 434371Z122834
Body Tag: 71-43437 Z 01375
Engine Code: D/230?
Engine Serial: 171Z122834?

 

4 = Buick

34 = GS (can be GS350 or GS 455)

37 = 2 door coupe

1 = 1971 model

Z = Fremont California plant

 

67 = Burnished cinnamon body paint

F = dark brown vinyl top (confirm this)

 

D = '71 350-4bbl 260hp.
230 = Assembly Date Code
Engine serial number matches your VIN except for the "7" ?
The 1st number if you look closer is a "4"
4 = Buick
7 = ?
1 = 1971
and the rest you know already.....plus what Jim posted.

 

You guys are amazing, thanks a bunch, all of you!

 

I thought the "7" was a "Z" and matches the Z as the location of the build?

 

Just a little fun fact, I live in Newark, it's surrounded by the city of Fremont.
I drive by the factory all the time (now Tesla), it's nice to bring the car back home where it was born.

 

And this is why I'm confused.
BTW, look at the picture I provided, it does say D/230 from what I can see.

 

I don't see where the mention of "SD" is in any post. There is not an SD in '71. The S would represent 1970 and there is not a code D in '70.
D = in 1971 the code for a 350-4bbl with 260hp.
B = in 1971 is the code for a 350-4bbl also with 260hp
Either was used according to Buick so your stamping code would either "TB" or "TD" and of course the "T" = 1971
In January of 1970 Buick stated that "TD" was used in Skylarks,Sportwagons, LeSabres and GS models. In Sept. of 1970
Buick stated that "TD" was LeSabre only.
His VIN matches the stamping so if my old eyes are correct it's a match.

 

The pic referenced a "D" it looks like he has not scraped enough to find the "T".
I do not see any reference of an "S" code in any post.

 

Do you think it's necessary to try and find the S, or is it safe to assume that D/230 is correct for 4bbl 350-260hp?

 

Also, what is the last 3 numbers of the Body tag mean? Should it be in the VIN?

 

Sir, your car has been identified as a 1971. Your VIN in 2 locations says it's a '71. If you scrape you will or will not find the "T". BUT you will not find an "S".
There is no assume its a 350-4bbl. In 1971 the "D" = 350-4bbl 260hp.
There is not a "D" code in 1970.
The complete stamp code would read "T D" = a 1971 350-4bbl 260hp.
Other than this I do not know what else to tell you.

 

Hey, that's more than I knew earlier today.

 

Jason, I see what your talking about now. Like I said, these old eyes missed that.
Something tells me this car is not 49 state local. Body Style "SD"....are they calling
this 2dr coupe a sedan?....

 

I actually took a good look at the engine code, and it looks like there is a T all the way to the left. It’s hard to see, but I do think it is T D/230.

 

Just to add what Jim has already posted,

What your Fisher Plate says, hope this helps.

71 = 1971
4 = Buick
34 = GS ( 3400 Series )
37 = 2dr H.T.
Z = Fremont Assembly Plant
01375 = Fisher Body Build Sequence Number
156 = Sandalwood Vinyl Notchback Interior
B80 = RPO Code for Drip Rail Moldings
67 = Burnished Cinnamon Lower Exterior Body Color
F = Dark Brown Vinyl Top
04A = Assembly Time Code 04 = April, A = 1st Week 1971
The other 2 sets of numbers are Data Processing Numbers
Used internally at Fremont.