A Few Arca Quick Release Questions ???

1. Are Manfrotto and Arca Swiss Interchangeable ?
I at first had assumed that they were; but then, some of the things I read make me wonder otherwise.
Some say the Manfrotto is thicker and therefore the two are not compatible with each other.
Although I have never had either in my hand, I am very well versed in the dovetail concept and would think that, so long as a plate was not wider than the clamp, the clamp would tighten onto the plate, regardless of the thickness of the plate; am I right ?
(Although it would be best if the dovetail angle of both components were the same, in most cases, mismatched angles would still clamp.)

2. Gimbals have the plate oriented fore-and-aft; yet, in most of the pictures of plates, they are attached to the camera abeam/ transverse/side-to-side; are there reasons for this ?
I would assume a fore-and-aft orientation of the plate would be preferable; or, do heads other than gimbals necessitate the abeam orientation ?

Please excuse my ignorance; for, as I already said, I have never yet had my hands on, nor my eyes directly on, any of the dovetail style mounts.

Thanks for reading and all help is appreciated.

Manfrotto and Arca are not interchangeable.
Several years ago Manfrotto released their 'top lock' system that allows Arca plates to work in their clamps. But you can't use Manfrotto plates in an Arca clamp.

I'm sure someone has mounted a camera on a Gimbal, but I have never seen it.
When using a Gimbal, the lens is mounted to the Gimbal, rather than mounting the camera to the Gimbal.

To mount a camera to a Gimbal, a lens plate or a universal plate would be fitted to the camera so it could be rotated 90 degrees to normal camera plate orientation.

3. I figure a long Arca-Swiss plate will work in a short clamp/base.
I see Arca-Swiss clamp/base in varying lengths.
I figure the longer the better = more support against rocking and more clamping surface.
Will a short plate work in a long clamp/base ?

I found this to explain the differences between Manfrotto and Arca-Swiss very well:

https://www.acratech.n​et …-manfrotto-camera-plates/

Any length plate in any length clamp is OK.

4. The Utebit 50mm Clamp-Base I just received has a 0-center scale on the clamp base, but no reference whatsoever on the included simple plate.
What purpose does the scale serve ?
Thanks.

https://www.amazon.com …sc=1&ref_=lv_ov​_lig_dp_it

I used this to adapt the unique round adapter on my SLIK 700DX Panhead to accept Arca Swiss.
I really like the ease and safety of the SLIK round adapter system and this conversion gives me the best of both worlds.
I can remove the converted SLIK circular adapter from the tripod, clamp it on the camera's Arca Swiss plate, and safely drop the whole works into the Panhead's receptacle.

This has turned out to be one of my better ideas.