I hesitate to comment here because it's obvious you are treading in very unfamiliar territory for you. Yes...the trans...and everything else from the back of the block to the rear differential must come out.
I would highly recommend you get a good shop manual for your application. It will be invaluable. Many people think a clutch job is simple nut and bolt work. IT IS NOT!!! A good clutch job is very expensive and takes experience and a trained eye to see what is going on and what needs to be repaired/replaced. You may end up having to replace a rear main seal, a front trans seal, etc. The clutch actuating system...whether it be hydraulic or mechanical must be inspected and replaced as necessary. The bearing retainer almost always should be replaced as the throw out bearing must move smoothly on this surface...and it is a wear surface. The flywheel MUST be surfaced or replaced. It must be measured after surfacing to see how much material has been removed and a shim used if necessary to bring the clutch surface back out to the proper distance. See Pioneer for flywheel shims. But if I do a clutch job I don't know the history of the vehicle, I replace the flywheel. And if I do know the history, anything more than a light surfacing dictates a new flywheel. You must replace the pilot bearing/bushing. Inspect the trans input shaft and look for damage. Inspect all bolts and guide pins for damage. You will need an alignment tool...usually comes with a new clutch assy. And you don't want to be doing this again for a long time...so buy QUALITY parts. Spend the money right the first time.
I say all this because you need to keep in mind that a clutch and flywheel assy are not light components. They have some mass to them. I don't know what your engine revs to, but think about something breaking or coming loose at that rpm. It can literally come right through the cab of the truck. I personally saw a flywheel assy on a race car go right throught the windshield. This was after it went through the bellhousing, floorboard, took off part of his shoe and two toes, the dash board, and out the window. That is why scattershields are required in all stick shift race cars. So it can be a big safety item...so you want to do it right.
I wouldn't be afraid to tackle this if I were you if you have a good factory shop manual and/or some good experienced help. You should learn a lot and benefit from it. Otherwise, you would probably be money ahead to have a good shop do it for you. Good luck!!
