A hatori 650 has three baffles and the baffle welds are visible from the outside. I don't think that is a 650. I have pipe on an Enya 60XL GP that looks a lot like that one. I think it was made by Enya. Is there one threaded hole for a pressure tap, maybe just stopped up with a screw? Shine a flashlight down through the inlet and see if it a coned baffle or a flat baffle. If it is a flat baffle pipe, then you can use the distance to the baffle to set up the pipe.