all 69's had a vin# on the passenger side by the mount. If you don't have the original engine, it doesn't matter. It is very unwise to grind down a vin# to pass it off as original. it is very Illegal. all 69 cudas had an HP stamp. I have two and both are stamped HP. My 68 and 69 dart 383's are also stamped HP. 68's had their vin# on the driver side behind linkage on engine edge and trans lip. on the good side, these cars are so rare and valuable that it doesn't matter anyway. Just restore the car and have fun, close is good enough on these old A body cars, and they are a great Investment! Also, the S after 383 is in reference to the fuel quality. my 340r was regular, low compression 1972, and my 69' had a P' for premium fuel, which referred to the 10.5 compression engine. if you look at 273 and 318 engines, they all have an R for regular.
