Use yer meter!
Hand held meter set at 80, then be accurate in setting your aperture, don't get lazy and let it slip into the full or 1/2 stop click position if it's not supposed to be there....
If shooting in full sunlight, 1/250th at F/8 and a half is the norm, but as soon as it is side lit, open up a 1/4 to 1/3rd. Snow cover can add a 1/4 stop, lots of spill. Full sunlight in a otherwise dark forest will be a tad less than sunny F/16 due to the light being sucked out by dark surroundings.
Because of a weak cyan layer, Kodachrome often lacks pop on those milky clear winter days between 10AM and 2 PM. Before or after that, it comes to life as natural polarization has a greater effect.
In fact, today is one of those days...I am looking out the window and there is lots of sun, but the sky is milky, some high cirrus clouds, not a lot of color even to my eyes. Unless the subject screamed for me to shoot, I would be passing on shooting Kodachrome today..
Remember, everything in life is a reflector, even the clothes you choose to wear. The color tone of one building over another can have a great impact on what your final shot will look like. Often the best sunset photo is not the sunset it self, but what or who it is lighting up with the soft glow of a pink sky..
Go on Flicker and study some of the Kodachrome shots, namely the color content and exposures. You will quickly see where Kodachrome is shinning and where it is not. This pool is a good place:
http://www.flickr.com/groups/kodachrome/pool/
My stuff is a good place to see how I look for color and form in using the film and for the record, I rarely bracket anymore:
http://www.flickr.com/photos/23585735@N06/sets/72157612226326832/
And:
http://www.flickr.com/photos/23585735@N06/sets/72157613088832861/
Part of the reason I formed the project for others to shoot is because I find Kodachrome to be a great teacher of light and form. What you got is what you get, no going back into RAW and tweaking the color, tone or contrast.
Hope this helps,
Dan