Monkey Wards was like a Sears Craftsman, Wards didn't actually build the tractor, they farmed it out. The "gil" in the serial # tells you it's really a
GILSON..... I can't really tell from the photo you posted with the side view, but it looks like a
Gilson 53003 or 53004 S-14 to me. Gilson liked to run Tecumseh/Peerless transmissions and that sounds like bad news because Tecumseh is long gone, but Tecumseh owned Peerless so you can start figuring out the transmission from there...... My wild guess would be it's either a 2400, or 2500 series Peerless. I've attached a link to a Peerless Service Manual. The Peerless 2400 and 2500 series of hydros are covered in chapters 15 & 16. The main difference to ID if I'm correct is ....... On the 2400 Peerless the hydraulic motor mounts on the right side of the transaxle. On a 2500 Peerless the hydraulic motor mounts to the front of the transaxle. My guess would also be it ran either an Eaton 10, or Eaton 11 hydraulic pump..... I'm doing a lot of guessing without actually seeing the transaxle, but maybe this will help....
Gilson S-14
Tecumseh/Peerless Transaxle PDF