tuning an antenna without a SWR meter

Not sure if this has been asked before but is it possible to tune an antenna somewhat close without using a swr meter? I have one of the older Cobra 25 LTD Classics with the mic plug on the side rather than the front. It doesnt have the SWR meter on the power gauge but if anybody knows, where should the power needle be when I key the mic on a properly tuned antenna? As of right know, I have a 2010 Cascadia and I'm using all factory wiring minus the passenger side antenna because it seems like i get better results because if duals need to be certain distance apart, then the duals on here arent even close to being far enough apart being mounted to the side of the sleeper rather than at each end of the mirrors. The antenna Im using is one of those fancy tunable whips that has the two rather large coils close to the base of the antenna. The overall length of the antenna is prolly 4 feet. It seems to work ok since it sticks above the cab a lot further than the short, 3 foot stockers that were on here, but it seems like it could be better if it were properly tuned. Right when I put it on, I was still able to talk to somebody fairly loud and clear with about a mile to a mile and a half of distance between us. That good? Acceptible? Need o be improved?

 

Even on a system that has factory wiring and mounts and with one of them multiplexer boxes that splits the AM/FM radio signal from the CB signal?

I got nothing wrong with Francis, but this antenna Im using now was free. Does Francis make Antennas that arent made with a fiberglass shaft? The reason for asking is because since I chose to use the factory mounts, a four-foot antenna mounted in that spot would probly be takin out low-flyin aircraft, if ya know what i mean and with the style of antenna I have, its one of those flexible wire whips that has a lot more give in it.

 

Besides, I was still hittin an occasional limb or two with the 3-footers I had on here before.