From experience I've noticed that when I installed the OEM Sirius antenna and it wasn't in contact with the steel part of the roof I lost reception.. I since then made sure that the sticky side was sticking good to maintain contact with the roof and never had an issue again...

I suggest you get a good metal liner instead of the tape. The fact the you have it inside the spoiler doesn't help with the reception...

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TQ2K


'04 N62 - Alpine White/Truffle
'03 S62 - Petrol Mica/Champagne
'97 S52/4/5 - Alpine White/Dove
'91 M42/4/5 - Brilliantrot/Tan