It will drop right on. If your older motor is a 2.0 150 tha exhaust openings will be good ta go. Use a power head gasket for tha later model 150. You might wanna check tha stud length on tha front two and tha back four (all tha short ones). There also may be a difference in gear ratio's. If both are 2.0 motors both should be 2 ta 1's. If both are "plain jane" carb 150's and neither are a "XR whatever" motor they should be tha same.......
