I just bought this tractor and I need some help.The serial tag has 4 67 Y on it. I can"t find any block # other than a casting # 878234R1 and another # on the other side 503C 2091. I"m sure it has the wrong carb because the opening points toward the seat instead of the front and it"s tag has 378196R91 on it. I have the operator manual and I got a parts book too. I know the carb # is wrong but I don"t know what it"s off of. The parts book # is 388424R92 for the 263 engine and 396197R92 for the 291 engine. Did they only use the 263 engine or did someone put in a different engine. Someone wrote in the manual C282 engine. Can someone tell me what year it is and what it"s worth? Thanks I posted some pics of it in the gallery.