First let me say that time isn't an issue. We'll be staying in Kenmare and have all day to get there.
I see at least three and maybe four ways to get from Letterfrack to Kenmare.
We could use the M18 to get to Limerick and then south on the N21.
Or we could take the N20 from Limerick south to the N72.
Or the N52 east from Galway and go through Portumna and south skirting Limerick city to the east.
Another option seems to be the ferry from Killmer to Tarbert.
We're looking for the most photographically interesting route and don't mind going slowly.
As always, thanks for any suggestions.