Yeah, a clutch swap is a pretty big job, but if you have access to a car hoist and transmission jack, then it's a lot easier. You'll want to have a clutch alignment tool for when you tighten the pressure plate down against the flywheel. It's always a good idea to get the flywheel resurfaced and replace both clutch bearings as well as the front seal on the transmission while you're in there. The later model Mustangs use automatic trans fluid and I believe it's 3 quarts. It's a good idea to drain the trans before you remove it to lighten it a bit plus prevent spilling if it gets tipped. Personally, I'd pay to have it done, but if you have the means and motivation then have at it!