1942 pinouts from gopstein@bms.com (Rich Gopstein)

Solder Side		Parts Side

GND		A 1	GND
+5		B 2	+5
+12		C 3	+12
GND		D 4	GND
Speaker -	E 5	Speaker -
Speaker +	F 6	Speaker +
Coin Counter -	H 7	Coin Counter +
key		J 8	key
Shoot 1		K 9	Up 1
Down 1		L 10	Left 1
Right 1		M 11	GND 1
Shoot 2		N 12	Up 2
Down 2		P 13	Left 2
Right 2		R 14	GND 2
2 Player start	S 15	GND
1 Player start	T 16	GND
Coin Switch	U 17	GND
Service Switch	V 18	GND
unused		W 19	Loop 1
unused		X 20	Loop 2
unused		Y 21	Vid GND
Sync		Z 22	Red
Green		a 23	Blue
unused		b 24	unused
unused		c 25	unused
unused		d 26	unused
+5		e 27	*
GND		f 28	GND

* Pin 27 was blank in the manual, but it's probably +5v.