As I understand it, a vintage machine is less than 100 years old whereas an antique machine is more than 100 years old. I'm not sure of the number at the other end - does anyone know if it is 40 years old that the vintage machine needs to be, or maybe 60?
You don't need to lower feed dogs to fmq. If yours won't lower, you might try a Stoppax darning attachment, often available on ebay. That will make any machine fmq. I suggest you do not attempt to remove any feed dogs to fmq. Those old screws are likely to break off. Ask me how I know.
There is a pair of pliers made specifically for putting a leather belt on a treadle machine. Anyone know where to get one? I see them on ebay from time to time.
Cricket