'95 Silverado A/C vent problem

Guys, how would I troubleshoot the A/C vent switch problem when blower works great; A/C works great, but little or no air is coming through any of the vents? What would I check first?

Check for a blockage in/around the blower motor. My dad's Explorer sat for a long time, and a mouse built a nest in the blower wheel. It sounded normal, but wasn't flowing any air.

Nope. Not a clog. Also noticed the dome and under lights not working. Pulled the fuze panel door off and lights came on. Checked a/c after and blows you off the seat now. Suspect a lose connect on the box. tks