First of all I am assuming your 1086 is about the same as my 1486 and if so, the fuse compartment is located directly below the instrument cluster, in the center, near the platform floor. The cover has several screws holding it on.
On mine the fuse clips have gotten loose over the years and the fuses don't always make good contact and I loose power to one circuit or another.
Again, on mine, the primary power comes from a connection to one of the batteries (on the right hand side, I think). I have pulled the wire loose before and lost all power and another time the wire connection corroded off.
If you don't find the problem at either of these two places the next step would be to pull the instrument cluster out and look for broken wire terminals. These are pretty simple fixes so don't be intimidated with the electricity. If you need any more help I'll walk you through it.