About a month ago my marea w/end 100SV started to run a bit rough its also not starting as well as it used to even when warmed up:bang: . anyone got any ideas. also does anyone know what the proper spark plug gaps should be?

Spark plug gap is 0.8mm.
Any other symptoms?

also a squealing clutch and it feels a bit down on power a times.

With generic symptons you start with visual checks of your ignition and colour of plugs.
Although much maligned a fuel additive can help if the fuel system has never been cleaned or not being cleaned recently.
If you can't find any probs with that then we'll have a look at sensors.