If you are destined to use PROC IMPORT rather than coding your own DATA step, one technique that may work, given your example input file, would be to append a unique prefix character to the CUST_ID field and then strip off the character after the data is read up. So, if you do not have control of the layout of your raw, input data creating, then you would need to code a DATA step such as:
DATA _NULL_;
INFILE INDATA;
INPUT;
PUT @1 'Z' _INFILE_;
RUN;
Then, after the PROC IMPORT, you would need to code some DATA step logic to strip off the leading "Z" character with something like:
CUST_ID = SUBSTR(CUST_ID,2);
I typically use this technique when generating Excel data with SAS, as CSV-formatted, delimited files, adding a single-quote character prefix, so Excel will treat the data as text during wizard-import without my telling it to do so.
Scott Barry
SBBWorks, Inc.