Hot Rods need help identifying this

Sorry it took so long to get back to you. I checked and it does have PTO plate so it is a sm420, however I was unable to get in gear. Also I pulled the plugs in attempt to turn over the engine and #6 cyl. was full of water; not good. So if any body wants this running gear, you're welcome to it. Its located in N. Cal. Thanks to all for your help.