Carnac is correct. It's TB 11-5820-890-20-71, INSTALLATION INSTRUCTIONS FOR INSTALLATION KIT, ELECTRONIC EQUIPMENT MK-2378/VRC (NSN 5895-01-225-0518) (EIC: N/A) TO PERMIT INSTALLATION OF RADIO SET AN/VRC-87/88/90 SERIES IN M923, M924, M925, M926, M927, M928, M931, M932, M933 AND M936 TRUCK...