I picked up two of what I believe are 400 LP tractors. One is serial # 7028 S and has a LP tank from Western Tank Co out of Lubbock, Texas. There is no "C" on the serial tag, but it is the same tank mfgr that my factory 560LP has that does have a "C" in the serial number. The other is serial # 27087 S and has a LP tank from Wendland Tank Co out of San Angelo, Texas. Neither tractor has any emblems on them. Both have power steering that looks correct except the later one has its own power steering pump. Could either one be a factory LP tractor? How can I tell? Also, where do I find the head casting number? Thanks in advance for all your replies!