TD5 clutch

my friend has a 99 TD5 with the clutch slipping it had a new clutch just over a year ago his disco has a stage 2 upgrade. has anyone else had this problem? what clutch would you recommend?
he has been advised to change the flywheel what do you think?
is this a job that can be done by two men in a garage with a pit?

in 75% of the time the flywheel need changing they can get alot of play in them or in my case it was dished i did this job on my driveway the first time and took me all day i can do this job on the 4 post ramp at work in 3-4 (had it out 2 more times for other reasens) put 2 pieces of wood across the pit and pack the gear box off it then slide it back you need to get the box as low ass poss to let the hand brake drum get past the floor pan (we have a little trolly on the ramp that helps slide it back )