I have an excel spreadsheet consisting of columns of "patient ID's" and then various columns of "numerical values".

Some patient ID's are "DD-0002-0001PK" as an example. I Want to add a "L" to some of those sample names....like "DD-0002-001PK-L" how can I do that?

I can't just put ="L"&A1, because my values are text and if I do that it just changes it to a 0, and I need those ID labels, but I don't want to have to go back manually and type in "L". Is there anyway that I can put "L" on the back of the first 40 ID's?