Cheers for this! I'm pretty sure I only knocked 1 or two shims off, that where definitely from the top side of the gears. Looking under one, seems there's atleast two shims. Which has thrown my theory of copying another 9x series shimming setup out the window! Bugger!
Wow, thanks for the in-depth info, I really appreciate it!
I've done the typical thing of tinkering a day before a game day, which I'm now heavily regretting, but lesson learnt I spose.
I'll see what I can achieve keeping this information in mind.