Beaky,

Went out and check the voltages, they are as follows (pins go from right to left on the machine)

Player 3

Pins 1 - 16
-0.8   3.7   4.2   3.8   9.1   82   -93   3.2   2.9   3.2   0   6.4   2.3   3.8   0   5.4

Pins 24 - 39
3.2   0   6.4   3.8   6.4   0   5.4   -95   3.2   1.1   83   0   6.5   0   6.5   -1.3

Player 4
Pins 1-16
-1.4   6.7   0.5   6.8   16.7   17.4   -10.8   5.4   0   5.4   3.5   6.5   0   6.4   1.9   5.5

Pins 24-39
5.5   1.9   6.4   2.5   6.5   1.6   -3.7   -12.5   -3.6   -0.8   18.3   -1.5   3.7   -1.9   3.7   -2.1

The other thing i noticed is that some seemed to fluctuate a bit, dunno if this was when the display was meant to be lit up during attract mode?