I have my grandfathers Farmall 140, serial number 34779. I'm trying to determine if it is worth sinking any money into it to get it back into working condition for a small hobby farm/field maintenance. I know that it needs a new battery ( I believe it needs a 6 volt battery), and new front and rear tires. It has not been started in over 18 years and has been sitting with fuel and other liquids this whole time. any recommendations on if it's worth the investment or looking for a newer tractor would be much appreciated. Thank you!