Version 2.0 of this modification supports high score save for each game in thier own high score table.  The high score is 
saved on an nvram that is wired on to the board.  The nvram used can either be a 48z02 or a DS1220 (both can be found 
on the store page).  My initial thought was to plug the nvram into one of the empty eprom sockets and just 
wire up the w/r and CS lines.  For several reasons that did not work but if you wire up the nvram to the 2114 ram (or make 
an adapter) it will work.  There are some creative ways to get the nvram on the board, if you think of any send them to me
and I will post them here.  


Here is how the nvram (48z02/DS1220) needs to be connected:


NVRAM pin1   (A7) ->  2114 (4K) pin17                                       NVRAM pin24 (Vcc)  ->  Any +5
NVRAM pin2   (A6) ->  2114 (4K) pin1                                         NVRAM pin23 (A8)   ->  2114 (4K) pin16
NVRAM pin3   (A5) ->  2114 (4K) pin2                                         NVRAM pin22 (A9)   ->  2114 (4K) pin15
NVRAM pin4   (A4) ->  2114 (4K) pin3                                         NVRAM pin21 (/W)  ->  2114 (4K) pin10
NVRAM pin5   (A3) ->  2114 (4K) pin4                                         NVRAM pin20 (/G)   ->  74ls139 (5L) pin10
NVRAM pin6   (A2) ->  2114 (4K) pin7                                         NVRAM pin19 (A10) ->  Any GND
NVRAM pin7   (A1) ->  2114 (4K) pin6                                         NVRAM pin18 (/E)   ->  74ls139 (5L) pin10
NVRAM pin8   (A0) ->  2114 (4K) pin5                                         NVRAM pin17 (D7)   ->  2114 (4K) pin11
NVRAM pin9   (D0) ->  2114 (4N) pin14                                       NVRAM pin16 (D6)   ->  2114 (4K) pin12
NVRAM pin10 (D1) ->  2114 (4N) pin13                                       NVRAM pin15 (D5)   ->  2114 (4K) pin13
NVRAM pin11 (D2) ->  2114 (4N) pin12                                       NVRAM pin14 (D4)   ->  2114 (4K) pin14
NVRAM pin12 (Vss) -> Any GND                                                NVRAM pin13 (D3)   ->  2114 (4N) pin11
 
  Here is a great example of an adapter courtesy of Slava Madrit
  
Adapter2  Adapter1
  
Here is a great example of an adapter courtesy of Mike Fuchs
Adapter3