Most of that info was available on the Drip Forum but it seems that even backdoor access has been nixed . Fortunately, I saved a lot of info in my files and here's what I found;
"Sowter OT is wired out of phase (blue and grey) for some people."
"Sowter says grey wire is hot."
Take that for what you will. I bypassed the pad and wired mine directly to the destination in the circuit so I can't tell you which goes where without pulling it apart.
Edit; I found this which Sowter sent me;
https://www.dropbox.com/s/nqbvr9iof5hdttx/9185s.pdf?dl=0
Regarding the meter, there's a place in the states that makes them but I'll be damned if I'm going to spend $125+shipping for a meter so I picked up an NOS Wesson 200uaDC meter that looks just like the original for $25 on ebay. Spent 30 cents to have this;
https://www.dropbox.com/s/ldw55grwpvitowl/STALEVELMETER.jpg?dl=0 printed up, and it saved me over $100. I tried to find the box to look up the model # but I don't know where I stashed it. 200uaDC meters with that housing show up on ebay every couple weeks or so.
The manual does not properly impress upon the reader that you can easily go wrong without proper padding on the unit. Mine didn't work for 6 months because I followed a couple of the options in the manual. In the end, I stripped off the input pad, used a Mallory T-600 instead of a PEC pot, and padded the output a little. The output on these can drive a guitar amp so you really have to get it under control or you may be overdriving your A/D at only 15% on the output knob. I don't recall what my output turned out to be (in terms of resistor values) but if you get a Mallory in there and need help, I'll open the case and check. As is, I'm usually around 40 to 60% on the knob when tracking, less when mixing.
With no input pad, I can get 10dB reduction with the input knob around 40 to 60% open on most sources.
Both those are very comfortable levels for me as I have a lot of room to play with in either direction.
Being that the input feeds the 6386 directly I don't know that you could make it a mic preamp without creating another stage. Otherwise, you'd be a little out of control and implementing compression haphazardly. With something like an LA-2A, you can adjust the compression separately, which is why those work as mic preamps.
Hope that helps.
