Not quite sure what you are dealing with but whatever adhesive/glue will only be as strong as the surface you deal with. Do you intend to cut thru whatever the roof material is to get to metal to stick this to? Your call on that.
Permatex Clear Adhesive Sealant by brand has proven to me to be outstanding and not brittle - it's NOT paintable but works well in extremes of temp. It needs to be secured in place about 24 hours for full strength. It's permanent to the point you would have to razor blade it off if ever needed.
Another sold everywhere is faster called GOOP by brand - hardware stores, some automotive, Wal-Mart etc. Packaging states high end temp range of just 150 degrees F which should be enough - untested by me at anything over that. Either tolerate cold - the Goop can be painted.
There's an assortment in some auto parts stores which should state their properties for what you want.
Again - not sure what you are dealing with. If this is a felted headliner that alone won't be very strong so you would want to anchor to metal above it,
T
Tom Greenleaf - MetroWest Boston - USA
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http://www.autoacsystems.com/tomgreenleaf/