While I have my dash apart on the 96 burb, I want to look at why I have low air flow through the dash air ducts. It seems like air mostly comes out the floor vents and some through the dash.

Ideas?

You may have some flaps not sealing good but think I would replace the fan motor before getting too carried away tearing things apart. They do get weak with age and start slowing down especially when hot.

yeah, as above or it could be the selector switch which is vacuum powered iirc...therefore possible vacuum leak.

All electric actuators on his burb.... check for actuators opening and closing fully, second thing is to look at evaporator core and see if it's covered with dirt, they had no cabin air filters on them