Yeah, that’s the approach I use too. Eventually I’ll have 2-3 versions of my resume/CV, and a file of typical paragraphs to put in a cover letter. Ideally I’ll have some kind of connection to the company, like: “in a conversation with (Name) at (conference), I learned of your work in (whatever)” or “I am familiar with (product/process) from applying it to my work on (previous work).” Whenever I’m hiring, that sort of cover letter tells me that at least they’ve taken the time to learn about the company, so it’s less likely a waste of time to interview them.