Greybeard, not sure why you're keen to see the reverse side , but here you go.
Becauses its a useful resource.
A) A person can ID what a proper one looks like if you have sample to look at, or run across one for sale (Or hanging up in a garage somewhere
B) it gives useful reference material if you have or find one thats damaged, missing parts or modified
C) a clever lad can fab or make their own IE: Copy/reverse engineer. Might not be the exact same or even a 1 off custom but at least you have a reference point as "This is original/stock" and can go from there.
In the Air Force they were very strict on Aircraft and munitions/weapons that *IF* you followed the "Technical Order" or TO which was basically the workshop manual then you were covered and competent.
(Not doing so could result in Court Martial or getting someone killed/maimed so always good to follow the rules.)
However, as well know using workshop manuals, SOMETIMES its just not 100% clear exactly what you are doing. So, on the flightline we had a slang-derogatory term I will skip naming, But it was basically go consult one of the other acft or systems on the flightline. Wing: 20 acft, sometimes 12 Squadron 24.
If you got called out or questioned it was simple enough to defend your decisions that the other acft were operational with the same wiring arrangment, or alignment, or which side the spacer fits.
Which is a long way to say, we dont have a fleet of similar vehicles to compare with, so good photos are a godsend when sitting in a shed in Armpit Oklahoma, Or MooseJaw Canada and havent the faintest idea what the part looks like.
As to the fab, excellent job, The original was formed either on a Buck, or stamped on a Die for the body, Totally acceptable how your fab guy constructed it.
**Its an airbox fer christs sake, not the gyro for the Mars rover**
Since your fab source is not interested in commercial volume, whats the chance of making templates-tracings of the parts and posting them? All the parts can be made from flat sheet stock and then welded and bent/formed. If you have an original, the fab guy is very unlikely to just free form winged it, clearly made construction paper/cardboard/hardy board templates.
I know from classes and prev fab, that when making templates you have to allow for shrinkage and growth when bending/forming.
When we did classes in fabbing gas tanks and metal forming, some fab guys wont allow others to copy their work, some willing do so.
Given the lack of resources, those who share such material are doing the vintage community and great service