This info is right out of the GM service manual and should be what you need. You can get by without the special tools, a wide flat screw driver and good pair of water pump pliers should work just as well. Thanks
Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.
Tighten Tighten the wiper motor screws to 7 N·m (62 lb in).
Tighten Tighten the wiper motor crank arm screw to 16 N·m (142 lb in).
Tighten Tighten the wiper drive system module screws to 10 N·m (88 lb in).