Firstly, thanks for any assistance. Situation is as follows: Older home with electric power coming in off above-ground pole. Connection runs from pole to detached garage (meter is on the garage side) then to a disconnect (fairly old I think) with 100A and 60A switches. 60A goes through wall to a small panel in the garage. 100A goes back up to another weatherhead and travels suspended to house (about 30 ft away). Neither meter, disconnect nor garage panel appear to be grounded to earth. In the home there is a 100A panel that is earth ground (8ft copper rod) and bonded to copper plumbing also. Bonding screw is installed and ground and neutral bars are connected. There are only 3 wires (2 hot and neutral) going from garage to house (again, suspended in the air, so no conduit). House panel has a 40A dual pole breaker that feeds a subpanel with only one breaker (also 40A DP) that goes to the A/C unit. My questions concern:

(1) whether the house panel should be treated as a subpanel (i.e. should I separate the ground and neutral bars)

(2) should the main disconnect and/or garage panel be earth grounded also? And

(3) should I remove the A/C subpanel (i.e. is it bad to have the two breakers is a row on a single circuit).

Thanks so much!