Unfortunately, what I know about this isn't good. A few years ago a grad student doing research on this sent out identical resumes to hundreds of employers, changing only the so-called applicant's age. The results were pretty bad, the older fake applicants got many fewer callbacks. Barbara Ehrenreich also has a book about trying to find a job as an older worker, although I haven't read it so I can't report on it.
On the bright side, older workers have a reputation for being really dependable and loyal to companies, so you could play this up. Also, make sure you're up to date on whatever software you'd need, or certificates or other credentials.