From the Guild guitar manual.

Due to the tremendous amount of tension exerted on the neck by the 12 strings, we suggest that you use a light-gauge string set, such as the Guild XL-1000 or L-1250 on your 12-string guitar.

Couldn't find a reference to the first set however the second is listed as follows:

Guild® L1250 12-string Acoustic Guitar Strings - Light gauges 010-049

I can't find the actual intermediate gauges for the above set but the following will not be too far off.

String Type    inch   mm

E-1st Steel   .010   0.254
E-2nd Steel   .010   0.254
B-3rd Steel   .014   0.356
B-4th Steel   .014   0.356
G-5th Wound   .023   0.584
G-6th Steel   .010   0.254
D-7th Wound   .029   0.737
D-8th Steel   .012   0.305
A-9th Wound   .038   0.965
A-10th Steel   .018   0.457
E-11th Wound   .049   1.245
E-12th Wound   .027   0.686


CC