Hope you save both combines from going to China Tom, with some time and patience you would certainly soon have one up and running, a combine behind each of your No2's would look well, you are young enough to achieve this and preserve some lovely old machines.
Ron Knight our "Combine King" here in UK has rebuilt many old combines much worse than the one you pictured and he uses them in the field too, it is remarkable what comes out of his workshop each year considering his age. His latest acquisition is a self propelled Marshall combine which is just a pile of rust at the moment.
Keep us posted of your progression with them, what motor is on there? is it Hurcules?