Actually, the pads are still there for the ROM SIMM, they just added the additional pads/lines to turn it into your second RAM SIMM slot! It's all the same bus, just different "Chip/SIMM select" lines, the ROM version was likely only 24 bit, maybe even 16 bit. With just a few rework wires, you could very likely hack your second RAM SIMM Slot . . .
. . . into a completely useless ROM SIMM Slot. :lol:
8-o . . . just thought of something! I'll bet you could do the "same" thing to the ROM SIMM slot! just add the jumper lines for the additional bits from the RAM SIMM! You'd need to use a wire wrap prototyping slot and clip common the legs to a workable length and the additional RAM signals/control lines down to nubbins for the jumper wires (shielded of course!) [
] ]'>
You could even fab an adapter PCB, assuming you can hijack third/fourth SIMM select lines, to make three/four slots out of . . .
:O }
:rambo: 
)
. . . into a completely useless ROM SIMM Slot. :lol:
8-o . . . just thought of something! I'll bet you could do the "same" thing to the ROM SIMM slot! just add the jumper lines for the additional bits from the RAM SIMM! You'd need to use a wire wrap prototyping slot and clip common the legs to a workable length and the additional RAM signals/control lines down to nubbins for the jumper wires (shielded of course!) [
] ]'>You could even fab an adapter PCB, assuming you can hijack third/fourth SIMM select lines, to make three/four slots out of . . .
:O }
:rambo: )