Let me expand, I didn't include the number of shifts or days. That hasn't been discussed here. Dearborn produced somewhere between 5,000 and 7,000 Mustangs a week. Times 50 weeks, that's between 250,000 and 350,000 Mustangs. A weeks worth of wrong way shock tower bolts on Mustangs would be a lot, between 5,000 and 7,000 units. That still a lot, but a low statistical anomaly.
Jim
If you note in my originally post, I indicated 'usually'. Fred's suggestion to check for a footprint in the metal is the best advice, assuming the inner fenders are original.
Statistically, the evidence supports that Dearborn, overwhelmingly, installed the bolts from the wheel well side.
Here's a few reference cars during the time period I found with the bolt installation that way. I found 2 cars with the bolts going the opposite, but both cars were restored and had an aftermarket monte carlo bar.
5F09C363719
5F07C363824
5F07T353199
5F07T378815
5F09C361750
5F09C375664
5F07T379135
5F08C374578
5F08C377299
5F08T352791
5F07A362125
5F07C357342
5F07C363824
5F07T265653
5F09A375253
5F09C363695
5F09C369492
5F09C370934
5F09K368804