You want pointers? Set your vehicle up like this and EVERYBODY will be pointing....
Don't get your hopes up very high because the Sonic is a teeny tiny car with very limited ground plane. The performance will be disappointing IMO. If you want to communicate, put the 2 meter antenna back on.
You sure did go from one extreme to another by going from a Ford Crown Vic to a Sonic. LOL
20 bucks on the roof will outperform $3000.00 on the trunk lid.