Someone will try it eventually lol. Thanks for responding!Well, yeah, it would have to be to accommodate the thickness of the gasket. Remember that the upper pan is not only a structural part of the engine block it also completes the mounting for the transmission. Even though it is probably just machined 1mm-2mm more, somewhere, we can't be totally sure, putting one on an earlier build engine might result in bolt holes and machined surfaces not aligning. Though I do wonder if it can be done and it would be a nice little upgrade. Someone would have to try and let us know.