Rack problem

I now have the official GRiSO luggage rack, and have drilled two holes in my back fairing and would like to install it.
Unfortunately, I have a bolt problem. I have 4 bolts, 2 are 3 inches long and 2 are one inch long. The three inchers will probably work for the top brace of the rack but the one inch bolts have no  chance of reaching the threads on each side. Does anyone know what the proper lengths are for these?

I've never installed the GRiSO factory rack, but on principal, I would switch your configuration.

Installed mine last week, after wondering if it was even supposed to fit.
Small serrated spring washers intended under each screw, now coated with antiseize.
There are also 4 rubber cups/grommets which can be used to cover the holes if the rack is removed.

The long screws are for the side, with their respective spacers between the rack and the subframe on the sides.
[You must be registered and logged in to see this image.]


The smaller screws are for the top and fit well inside the protruding flange of the rack.
[You must be registered and logged in to see this image.]

At the end of it all, with the seat on, my word the seat looks the business and rack integrates well.
[You must be registered and logged in to see this image.]

Gentlemen, I stand before you red faced. All bolts went where they were meant
to go with no problem! The rubber plugs for the holes in the rack add a nice touch.

It's an Italian thing, nobody understands...