How would you do this ?

I am ready to start painting the frame of the tractor ( including rear wheel casts and axles). Rims and tires are removed. the engine is completely painted so the engine and dash will be masked off. Seat is also removed and all sheet metal. My question is what would you paint first? Frame , wheels or axles. Also does anyone have any good techniques for masking. Also the tractor is a 6030.

I think i'd paint the frame first, at least one medium coat, then do the axles/housings, and do the wheels on both sides of the wheels, thats if they are still on the tractor, and also do all of that painting at the same time. do not step back tho, to inspect yer work--you'll get something stuck in the fresh paint if you do that.
If you have the wheels off, then you must do them by standing them up on something up off the floor, and you can turn them, as the twists and turns of the wheels can leave thin spots in the finish. If you try to do one side today and the other side tomorrow, then you will get a dry cast to the paint, unless you mask the painted side first, then paint.
I'd try to paint it all at the same time-resulting in no dry spots, or flattening out of the paint you did yesterday! If the tires are off, then the little unpainted spot on each wheel will be able to be touched up with a brush, after the wheel is dry. Another way to do the wheels is to roll them along, to make sure you have no thin spots. Then do the inside of the rim edges later with a brush, because you are sure to bang up the paint when you put the tires back on!