Theo that looks fantastic.
I am a little curious if you use a brush or paint from a can as your finish looks very smooth.
Personally I use a flap disk, prime the base and then a couple of coats of decent quality kill rust or similar.
I think I might have missed the use of wet and dry sandpaper like you mentioned to get the super smooth finish.
Anyway the mower looks fantastic and Im sure it will sell quick.