Cascadia Antenna Solutions

Your 40 inch mount could work fine supporting a dipole.

 

It's a metalized rubber ground strap that attaches to the frame (or metal) on the truck and drags on the pavement.

You can get them at an auto parts store.

 

Make the bad ground become irrelevant.
Then it won't hinder performance.
Notice the bracket that attaches to the truck is electrically isolated from antenna system.

 

I wouldn't trust that stud to hold everything together. This is more trustworthy. 3/8 bolt directly into solid chunk of stainless. No stud to fall apart.

 

So all i need to do is isolate the metal bracket from pole(red) and just attach as per normal an upside down ant (green)

 

Add a flat metal plate with a couple insulators to your existing bracket to isolate the whole antenna system from the vehicle. Negative half needs to be able to handle the power output from the radio.

 

Not even close.
Changes occur up top at the feedpoint. Remove antenna from extender. Add a couple insulators above and below, then add a plate, then drop a bolt through the entire assembly grounding the bolt to the top plate. Underneath add insulator then metal washer and nut. Make sure top plate is electrically isolated from the extension bracket.
Tighten. Top plate needs 2 holes drilled into it.
5/8 for one, and 3/8 for the other. Insert counterpoise upside down in 3/8 hole. Put nut on top. Add Predator 10k as normal.
Bolt both antennas to top plate

 

frig that..Easier to just mount and isolate with the skip shooters..That top plate is not big enough to do anything with and i really dont wanna add drag to that set up..
O well ya dont learn without asking..
Looked like rain earlier so i didnt bother..Tomorrow ill drag out my wilson ant(mirror mount) bracket and a 5 ft fs and the 4.5 ft firestick and go that route..

Rabbi..That idea makes me wanna tinker though..

 

If the plate on the extender is aluminum I would replace it with stainless for strength.

 

If you move the feedpoint to the red circle you will render that Predator 10k useless. (Which is fine) but then you will need to get rid of the extender and use the 7 foot skipshooter antenna.