If you have access to a small die grinder, use a medium Rolox disc, and you can buzz any remaining gasket material with no difficulty whatsoever... without nicking up the mating surfaces.
Also, use a gasket maker material, follow the directions, and you don't even need to buy a new gasket.
I bought the EBC off eBay for some $41 or $42. It works great and is 20% stronger.
So, Rolox to save time, and NOT nick up the metal surfaces. Use an inch pound torque wrench, no need for a gasket, if you use a gasket maker material.
It's a relatively easy 2 hour job... the re-installing of the throwout rod in the clutch, back into the clutch cover is probably the trickiest, or most careful part.
I just did mine maybe 2 or 3 weeks ago.