Leading Zeros in ACH Import

I am trying to import ACH template that has leading zeros in the routing numbers that keep getting dropped off when I convert the excel to a csv. Additionally, very large numbers are condensing to scientific notation with the wrong values when in csv.

I have tried converting the column to Text, creating a blank CSV and copying the data into that instead of convert excel to csv, and have even tried importing with the csv still open -- nothing seems to work.

Any ideas on how to go about this? Thank you.