Looking at the list numbers on car parked for 40 years Center carb is date coded may 1970. Both outer carbs seem to have a 1972 date beginning with a 2. All I can think is a warranty fix ?

The only picture I can see clearly is the last one. That date is the 204 day of 1970. So they are are correct for a 71 car.

Thought the first numeral was a 0 for 1970. Both out board carb start with a 2. Center carb is 0580, back is 2040 and front is 2080

No. It’s the last number is the year.

Better yet. Thanks

I agree last digit is the year

0 = 1970 or 1980 ('90, '00, etc.)

0580 is awful early for a 1971 carb - I'm betting 1980, car got new carbs shortly before it was last regularly used

are both outboards 4671? (fronts)

058 = Friday 2/27/70 or Wednesday 2/27/80 or Tuesday 2/27/90 or Sunday 2/27/00

204 = Thursday 7/23/70 or Tuesday 7/22/80 or Monday 7/23/90 or Saturday 7/22/00

208 = Monday 7/27/70 or Saturday 7/26/80 or Friday 7/27/90 or Wednesday 7/26/00

'80 & '00 are leap years

rarely if ever are dates found for a Saturday or Sunday - the small pics look too good for typical 50 year old used carburetors (what does the rest of the engine compartment look like?) - I'm leaning toward '90

I think Dans right. It's hard to read but if both outboards are the same number then they are probably 1980 release carb. I have some 340 like that I bought from Gratiott auto in the 80s for $199 for all three.

Doesn't make sense for newer carbs if parked in the seventies. What do these numbers on the top relate to?

Those are just casting numbers for id purposes. The dates stamped on the carbs were only for Holley purpose. The used them
For inventory and quality control. That’s all the dates codes numbers on anything do for that matter. They never intended that a bunch of car nerds would put more value on a car because it had its originally installed parts still on the car 50 years later.