Being a 1974, it is unlikely to have had Stroppe installed power steering on it. Stroppe used GM Saginaw boxes up until 1973, when Bronco power steering became an option. He simply had no other choice.
The installation of the GM box required the frame to be notched and was also accompanied by reinforcing wings, welded in at the front cross member. See the photo below.
Looking at your dual shock mount for the front end, it does look similar to the ones on my '72. How many holes are on that mount? Mine either has three or four. Memory fails me at the moment.
On your rollbar, there were two very similar styles during that time frame because the design was sold to another manufacturer (Smitty, Duff, I don't remember). The Stroppe bar had removable legs and fewer bolt holes on the feet than the knock off. IIRC, Stroppe bars had fewer than 20 bolt holes while the other had more.
The green paint underneath belies the fact that it is not a Baja edition, but I bet you already knew that. Because of that there will be no DSO indication. What is your DSO code? Mine is 71 (Los Angeles) and the production number puts it a few hundred units away from some Bajas in the '72 model year. Best I can figure, it shipped to LA where it was delivered to a dealer. Either before or after purchase it was taken over to Stroppe for mods.
Keep in mind Stroppe stopped building Bajas in either late '74 or early '75, which is why all the Denver edition Broncos carry Stroppe paint jobs. Left overs from when Stroppe called it quits.
I'd say if it was a California truck, there is a moderate chance it was handled by Stroppe. Anything outside of California and the chances start to drop off.
There are no official or unofficial numbers or records as to how many trucks were built as Bajas. IIRC there was a fire or just a lazy book keeper. So records on Stroppe "kit" Broncos (as Baja owners are fond of referring to those not wearing the Poppy, White, and Blue) would be even less likely.
Remind me next time we're at a breakfast together with our Broncos and we can compare notes.
I was actually enjoying your jabbing but when I got to your 
about what the post was about I thought you were pissed at me for desecrating the thread. I guess I took it wrong and well you know the rest. No apology needed on my end but I wish to offer you one. How about I buy the first couple of 
s next time we get together (unless it's at the breakfast, we'll 
bloody mary's).