Street signs in the Highlands / Middle Scotland

[neloon]

I guess I'd really appreciate some clarification on what sort of Gaelic those signs were, and the degree of similarity to the modern Irish Gaelic. Any info would be gratefully received!

For native speakers, Scots and Irish Gaelic are mutually intelligible and, indeed, Irish speakers appear frequently in (Scots) Gaelic radio/TV programs. The languages do, however, differ quite a lot in their orthography i.e. written forms.
Whether or not names appear in Gaelic is up to the local authority. The situation can be complicated slightly by the fact that, in the east of Scotland, many placenames are p-celtic (Pictish)- for example, I live near a village called Fintry which derives from "fion- tref" (the fair village) which would be well understood by Welsh speakers. Their are also many "aber" names where the q-Celtic Gaelic would be "inver". Over in the west, on the other hand, many placenames are of Norse origin.
Alan