I've been looking around trying to establish what was chromed and decided that while there has been discussion around it there seem to be few pictures. So here are some parts from my lat3 40. I figured it would be hard to photograph as the chrome is about gone and its hard to photo anyway, so the parts are on a piece of Styrofoam with a pencil mark indicating where the chrome stops. The parts are going to the chrome shop tomorrow. When I get the hood latch off I'll take a photo of that. May just replace it depending on the $$$ at the chrome shop
Throttle shaft. Chrome runs to just past the bend where it turns down

Gear shift, chrome runs part way down the shifter

Leveling box crank.

John,
With all the answers you received, all the items have been named. My 9N had some worn or pitted chrome, but you can definitely see what was chromed. To sum up your list and the others:
Radiator cap
knob on hood door
shifter about 1/3 down-the chrome stops at an angle
choke knob
knob only on hydraulic lift handle
knob only on leveling box crank
throttle shaft until it enters the dash.

Kelly Jewell is the one to ask. He hasn't posted here in a long while but if you do an archive search you can turn up his email. Or, call Don b at www.just8ns.com and get Kelly's phone number. He has restored a bunch of '39's including four (I think) aluminum hood '39's. Jason Grooms is another who would know - Don will have his phone number, too. Jason has an aluminum hood 9N and other '39's.

As Bob mentioned radiator cap. Also add the gas tank door knob and as I seem to recall from sitting on our 9N in the 40's the throttle quadrant.

Radiator cap, too.