My hair is naturally mid-brown, now lightly streaked with grey.
I used to have blonde highlights put in at hairdresser with a semipermanent tint overlaid to lighten it all over and reduce the impact of the greys. It has all grown out now and I like the slightly darker colour.
But not the greys - and I want to start doing it myself to save time and money.
I have bought some dark-blonde dye in the hope that it will make the grey look like blonde highlights and the brown will stay brown.
Well, home dyes are generally a shade or 2 darker than they say they will be, so dark blond will probably be light brown. I would think that would do the trick with your greys although it won't lighten your overall colour. If you're not happy with the result you could go a shade darker.
I have been dying my greys since my mid 30s and IME, nice & easy gives the best results. I would use a semi permanent to start off with.