The small town of Chiselville for which the bridge is named has an interesting history. At the pull off, you will see a green sign with a few historical facts about the history of Chiselville.
You will need information from this sign to obtain the final coordinates for this cache. As always, please be careful when you are approaching the final coordinates for a cache.
The final coordinates for this cache can be expressed as:
N 43 0A.BCD
W 073 0E.FGH
The values for A through H can be obtained by using the dates you see on the sign as follows:
A = Subtract the number of times the number "7" appears in all of the dates from the number of times the number "8" appears in all of the dates.
B = Sum of 1st two digits of the date on the 3rd line divided by 3
C = Sum of the 1st three digits of the last date you can see on the sign
D = Sum of the 3rd digit of the 3rd date and the 3rd digit of the 4th date and divide the result by 3
E = Add the last digit from each of the 1st four dates you see on the sign and then drop the 1st digit from the result.
F = Subtract the 3rd date from the 4th date and call then F1. Then subtract the 2nd date from the 1st date and call that F2. Then subtract F1 from F2 to get F.
G = Two of the digits from 0 through 9 do not appear in any of the dates on the sign. Add those digits together and then subtract from that number the digit that appears the most number of times across all of the dates.
H = Number of dates you can see on the sign
You can validate your puzzle solution with certitude.