This.....
Make a list of what needs doing and what parts you need to do each job. Prevention rather than cure. I had a load of things wrong with one of mine, i just got all the bits together and spent the day on it. If you don't want to hammer it all in a day, take a day to take it apart and put it all back together the next, taking your time.
While i was at it i dropped the oil etc...Get it all out of the way, if something comes up unexpected you can deal with it objectively.