M900 Suspension settings

I've just purchased a 1994 model m900 and after taking it out 2day on its maiden ride out. The handling was terrible the bike wallowed around corners and generally felt very unstable this was multiplied if the surface was uneven.

The front forks are about 15mm through the top yorks, I'm unsure if this correct?

The rose joints on the rear suspension brace are wound out about 15mm also, is this correct?

Please could anyone advise me on the optimum settings for quicker riding, also I'm about 12stone.

All advice will be greatly appreciated.
Thanks