Aftermarket tach in rally cluster 67-71

Would this one be the same?

https://www.autometer.com/3-3-4-tac...DlEzckKCrj-sQC4XS_hmqeTMJhBzO1OZxUlnWY5s-Ad-1

Drawing a blank on the necessary size, seems like 3 3/4" is too big. But maybe with the shell removed it works?