newRPL on HP 39gs

[RMollov]

I got a cheap new HP-39G to newRPL it and managed to flash it - hard task, (thank God I keep my old & trusty Windows 7 32 bit laptop), but now the keyboard legend problem, see above.
I've got an old (one of the very first) HP-49G+ which is not suitable for newRPL (eats batteries in no time), could it be used as a keyboard donor? The legend printed on the faceplate can be replaced by stickers, but would be great if I could use the actual keys. I assume keyboard scheme is identical to HP-49+ / 50.
Any ideas?

I want to build newRPL-Frankenstein.

Thanks in advance,

Cheers