Lexlover, I doubt you can see the starter bolts with the intake in place even using a mirror. Getting the starter off isn't particularly hard just slow. The bolts can be reached with a conventional boxend wrench once the intake is removed. You just can't get much of a swing on the wrench.
In my case the solenoid gave a hearty single click when the key was turned to start but the engine didn't even try to turn over. I checked with a meter and I had plenty of battery voltage and it didn't drop much when the solenoid clicked. This seemed to fit with starter brush failure as described in this forum. I might add that the problem occurred suddenly with no warning, one morning it just wouldn't turn over. It had started great the evening before.
I didn't tear down the old starter so I can't comment on how hard it is to change the brushes. As hard as it is to get to I felt it was better to just put in a rebuilt starter and forget it.
I bought an intake gasket set which includes the manifold to head gaskets and the gasket between the manifold upper and lower halves, and a water outlet gasket that I couldn't figure out why I would need. I also bought two gaskets for the water connector that goes between the heads at the rear. And of course the starter. The part numbers are in an earlier post in this thread.
Regards, Ed
Just to repeat info that has been in other posts in this thread and others on starter problems, if you get multiple clicking when you turn the key to start you likely have a low battery or corroded connections. If you get a single solid click but no engine movement then it is the starter.
Good Luck, Ed