You should just throw the card out and never do parvo or distemper again. 
Parvo, distemper and rabies have been proven by 5 years challenge and 7 years serology to be affective from one vaccine given after the mothers immunities have worn off. Parvo is mainly a puppy disease so I would skip that one entirely, but if you have concerns about distemper I would go at LEAST 5 years between vaccines and when the dog has had 2 as an adult never do them again if you don't feel comfortable forgoing them.
I don't want to get into this fight again, but you need to be careful and be sure of the brand of vaccine being used. Different adjuvents and a modified live vs a killed vaccine may change those times significantly. There simply needs to be more long term studies done. Unfortunately if the vaccines do last that long, it cuts into the pharmaceutical giants making money off the vaccines and other factors, so its a hot point for debate. I have a feeling its going to continue to be so.
But to answer your question, no a month or 6 months doesn't matter in an adult dog. The only reason for the puppy series is because the mothers passed on immunities don't wane off every animal at the same time so the series is to "catch" all of them. You could give one set of puppy vacs after 16-20 weeks and not even do a series. Then do a "booster" at a year to make sure that you did catch them without mother's interference. Only vaccinate for one thing at at time if possible if you do vaccinate and NEVER rabies with anything else, that is the worst vaccine for reactions and long term health problems.
Also remember, with what you wrote above you are making the assumption that a puppy has adequate passive transfer of immunity from the mother. If there is a problem with that, the only way that puppy is going to get immunity to a disease is by its own immune system being stimulated.
Currently their is the Rabies Challenge Study which is hoping to prove the rabies vaccine lasts to 5years and even longer and do away with the bullshit every 3 year requirement and the backward places that still require it annually. 
Which is most cities and towns in the US with animal control ordinances. No matter what your felings are on vaccinations, you need to remember that in some areas vaccinations ARE a government dictated entity. You choose to not follow the animal control laws, you are subject to any and all penalties that occur. Its that simple.
And for the record, I think this Rabies study is a very good thing.
And a good, safer way to "vaccinate" your dog for distemper and parvo is to take them around a recently vaccinated dog that is shedding the vaccine and they can acquire immunities the way nature intended with the immune system working the way it is supposed to and not being assaulted by a vaccine. The rabies vaccine supposedly doesn't shed but there have been a few dogs that have been titered for rabies that have NEVER been vaccinated for it. An explanation has not been given to my knowledge to explain how that is possible.[/color]
This approach is really playing with fire unless you are willing to have your dogs titers checked afterwards. Its dependant on too many variables: the vaccinated dog shedding, there being sufficient viral load to stimulate your dogs immunity, your dog coming in contact with the virus particles, the viral particles being shed unchanged in a way that actually stimulates your dogs immunity. The list goes on.
Shedding should only occur with modified live vaccines and in some cases it may not depending on if its a vectored virus or not. There is no explainable way for a killed vaccine to be shed.
