Please Don't Help Me

I need suggestions on how to nicely tell my boss not to help me. My hours are based on production running, and for the past few weeks they have run a 10 hour a day staggered shift. My boss does not care to come in any earlier than 8:30 am, so I have the 4:30 am start time. This means I'm gone by 1 and he takes over from 1-3. I try to get any testing needed done by the time I leave.
We have been swamped this week with extra testing for a new Customer. When new products start the testing most customers require is beyond obscene. We take it in stride as we know that once regular production starts the testing amounts will decrease. A customer has every right to demand the testing and documentation to cover all their bases. The past couple days I have met with him before leaving and let him know that I could finish whatever was necessary the next morning. Every day this week I have come in to a complete mess. Uncompleted paper work, samples unlabeled, and tests done completely wrong. It has taken me more time to figure out and clean up his mess than to do it myself.
The first two days I just did it without commenting. See at home I'm accused going back over what I ask someone to do. Well 9 times out of 10 there is an issue. Taking out the garbage means taking out all the garbage, vacuuming means the whole house-not just one room, doing the dishes means-all the dishes including the pots you used to cook. So by past practice it's easier to do it myself, rather than pretending to be happy that someone did a half ass job.
Today I think may be my final straw. I came in to a bigger mess than the past 3 days, two major tests that were done wrong, and crap laying all over the lab. No notes, no paperwork-nothing. This may be my punishment for not saying anything the first couple days. Maybe I will hide any samples I do not finish by the time I leave.
My boss has made it clear that his position is only temporary. I can tell he is bored with his job and therefore puts no effort into things. He is taking night courses and figures he'll be moving up soon. He becomes very defensive when questioned about anything and actually becomes somewhat snotty with customers. There was an awkward situation in the lab with the customer that he was called out on afterwards by our manager. So I'm not sure what to do about this situation.