You could use this pinout, try a couple of tests, take a R, say 100 ohms, and connect
power to the backlight pin thru the R to see if that matches pinout and backlight
comes on.
If it does then connect main power to display, and measure drop across 100 ohm to see
what display current drain is. I = V / R. If it looks like roughly the current drain of the
display, a few mA, then this pinout probably good. For the other I/O pins use a couple
of hundred ohms in series with display pins as protection to not destroy display if its not
what we think. And if display seems to work then remove R's. Typically with no input, but
powered up, you might see something like this (contrast pin not adjusted) :
Regards, Dana.