Agreed. Skip the NGP antenna if you don't absolutely need one (which you don't).
Best place to put a radio antenna is dead-center top of the metal cab using a thru-hole mount, or on a 4" or larger diameter (or multi-magnet) magnetic mount (aluminum or steel actually makes little difference as a ground plane, though you cannot stick magnetic-mount antennas to aluminum). 2nd-best place would be on a fender or the metal bed-rail. Avoid bumpers at all costs, CB antennas simply do not belong there.
Static however will always be a fact of life with CB (27 MHz) radios. There are limits to how much static should be tolerated though... Some noise will always be present no matter what, such as pulse-type noise from the engine ignition. A radio with a "noise blanker" can be very effective in blocking out this noise. However noise coming from things like the blower fan, wiper motor, and fuel pump will have to be eliminated at the source using a .01µF noise suppression capacitor (or capacitors). Additionally, HID or cheap LED lights can literally wipe out CB reception completely (as can some USB cig-lighter charge adapters).
External sources of noise exist as well (such as fluorescent lights with electronic ballasts) which nothing can be done about other than to move further away from them.
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My suggestion would be to straighten out your antenna situation before trying anything else (move the antenna to the cab roof or someplace where it will have a proper RF ground), and then reassess whether the static noise (and range) is still objectionable. Many times a good antenna with a good RF ground is all that is needed.
Also, have an antenna with a minimum length of 60", as shorter antennas (especially those less than 48") aren't much better than jamming an old steel coat hanger into your antenna mount.
Finally, don't worry about coaxial cable length, this will have little or no effect on anything if your antenna SWR is good (only thing is you want the cable to be short as practical due to signal loss within the cable). If your SWR changes significantly with different cable lengths, then this would indicate you have a problem at the antenna (most often an inadequate RF ground), which is something that should be addressed at the antenna, not with the cable.
SWR (standing wave ratio) testers are available for as little as $15, though I would recommend spending a little more on one, as you'll likely get something more accurate (better ones will also show you the output power (watts) of your transmitter as well).