Unfortunately, I found that site previously (and a couple others) that claim to have the manual and will give it to you after profering personal details. Unfortunately, after a further google search on this site (because it looked dodgy), it turns out that this is a phishing site. So dont use it. Always be careful and check before going to some of these sites, or posting them for people to follow.
In any case have found a source for a schematics and manual (835 manual, 835a schematic), so all good now, thanks for for having a look.
PS: But I do have it up and running, still need to weed out some noise from Ch1, but at least this should take out a lot of guess work for calibration and remove the need to reverse engineer. Pretty clean inside.