Filler neck arrived.
However, even though OuiBay , says it will fit my vehicle.....
the snap in mount is too large for the mounting hole
Here's what I did to correct that



The clip that holds the connector to the mount, is a separate piece, similar
to the original. However, It isn't as easily removed. and the snap-in clip is rectangular, where the original was sort of round and smaller

orig clip...
you can estimate it's size by the paper punch out above
The new clip (below) is rectangular, and is 1/2" x 3/4", and will not fit the
mount. at first I tried to cut off the corners, and that failed, so I cut it off flush with the base.


This method worked well for me.

Shown here, before a spritz of Primer, and a spritz of clear coat

I am not responsible for your work, should you try this, so...
Proceed at your own risk.

 

What motor is that? Lucky you for having a mount. That should support the neck when you push down to turn the cap. Mine is just suspended (4.7L) and when I replaced with an cheap ebay neck (looked like yours, sans the mount), it didn't last but a few months before the cheap studded part broke off and leaked. I purchased a Mopar part which came with hoses and all attached and have been good ever since. I'm mindful of not pushing down too hard.

 

Hey Dodgevity,

It is a 3.9L V6 SMPI engine according to the "Build sheet".
The mount is factory as far as I know, it mounts using the same two bolts
as the Power Steering Pump. It is definitely a help getting the cap on and off.
It is just a stamped steel mount, resembling this hastily drawn illustration