I think you need to be a little more specific.
Instrumental ROCK?
Not quite.
I do like Mattias Eklundh a lot though, although I don't much care for his album Freak Guitar. There are some good tracks on it, but unlike Ron Thal.. many of them just seem to be unifinished songs that I felt like throwing on there. I would compare it to Buckethead, but although his solo albums tend to have lots of little short songs, most of those are just for comedic value as far as I can tell.
If you want to hear Mattias Eklundh doing something a little more meaningful, check out his band Freak Kitchen, they have several albums out. I wouldn't quite call it heavy metal, maybe "quirky" metal.
Also a lot of people seem to think this guys new on the music scene, but not so! Freak Kitchen's first album (and my favorite by them) came out in 1994.