Fitting a set of rear 2 pot WRX calipers (non-brembo) to my car through some adapter brackets and was wondering if anyone had the torque specs for the calipers, as well as any suggestions for the brackets too. I can't seem to find any manuals with the correct rear calipers as they're all either Brembos or the sliding type. Thanks

To be fair, I do wonder about tightening certain fasteners with torque wrenches as you cannot (without crack testing) evaluate the condition of the fasteners and the parts being clamped.
When I started out in the motor trade over 45 years ago, the only time we used a torque wrench was for cylinder head bolts, hub nuts and wheel nuts. The rest of the time it was usually tightened to FT and you can almost feel the yield point of the tightened nut or bolt.
Caught a cold many years back when torquing up bolts only to find they sheared....can you guarantee the condition of the components, how the wrench is used correctly and is it calibrated accurately.
Also, the common problem is that if a NutGun has been used to tighten fasteners in the past then this can also stretch the bolts rendering them unusable.

In answer to your question, I would tighten them by hand (never use NutGuns as I see so many doing nowadays) and I would add a thin smear of nut or thread lock to ensure it doesn't work loose even if it is slightly under tightened. If you're using the correct wrenches, sockets, ratchet or breaker bar you will know when it is tight and seated correctly without killing it with brute force