'71 340 intake date code

[76orangewagon]

I was able to purchase the correct Mounds Rd style 3512100 intake manifold (Thanks Mccannix and Hemicuda), the one with the square hump on top of the #8 runner but cant seem to figure out the 2571 build date code. If anyone can help me out with what the 4 digit code is I would really appreciate it.

[6bblgt]

2/5/71

[76orangewagon]

2/5/71

Dan,
Perfect... Thanks for clearing that up. At first I thought 257 day of 71 but that would be a mid-September  date and didn't work for a 1971 only intake and then thought maybe 25th week of 1971. My exhaust manifolds are 1-15-1971 and 1-27-1971 so that's close enough for me.
Ross