SWR meter to tune the antenna and a cable to link between the CB and the SWR meter.

http://www.amazon.com/Radio-Astatic-Workman-Jumper-CX-3-PL-PL/dp/B00K87CFK8/ref=sr_1_10?ie=UTF8&qid=1417879671&sr=8-10&keywords=swr+meter

I would go for a different antenna. The Little Wilson isn't the best performing. Its all about how much wire you have in the air. This is better:

http://www.amazon.com/Wilson-Series-Magnetic-Antenna-Removable/dp/B003H3L3U8/ref=sr_1_5?ie=UTF8&qid=1417879632&sr=8-5&keywords=wilson+cb+antenna