it is a big job, i know it sounds silly, but it is. i did my 90, it took me a day and a half with a electric drill plugged into the mains with a wire brush thing on the end to get all the dirt off. then took me 2 hours to do a thorough job with the waxoyl.
worth it, but a pain in the behind. and big job and i hated it... dusty... just a messy job.