WTF Front Brakes?!?

I pulled off my front wheels today to take a look at my upper control arms. In a different thread, a member had noticed that my upper control arms had welds on them and I thought I'd better investigate. A previous owner had converted to BBP discs but I'm not sure what brakes they used to convert them? My car is a 70 Duster and I just assumed that the PO converted them using 73+ A body disc parts. Now I'm unsure of what I'm running?

Can anyone help ID these brakes and tell me why my control arms have been welded? Both sides appear that they've been welded. Thanks

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