Clutch and oil pressure?

I have a 94 Plymoth Laser 1.8L. I love this car. I use it for work only and its a fun drive. I need to replace the clutch. I know cause,if getting on it too hard rpms jump with no increase in speed, and it dont engage until just before releace of clutch pedal. Is it hard or is it like a few of my freinds say just lining up the new and old clutch? And my other question is my oil presseure drops when driving. It would be fine when just started,but the first stop light it goes down and really dont want too go up and if does its at or below the min mark. I do know some and how to work on engines just never messed with clucth.Thanks