A/C - Heater Blower

I have a 1989 Mazda B2200.
The blower motor stopped working about a year ago.
I ordered a new one and my mechanic installed it.
On High, the air barely blows out the vents, in all modes (A/C, Defrost and Heat).
Is there something going on that I need to know about to get more air to blow through the vents? The blower "sounds" like it is blowing a lot of air...

On these, the air first passes through the AC evaporator, that could be clogged. It was on my '88, same symptoms.

Some get clogged due to leaves or debris, mine was clogged from refrigeration oil leak mixed with dirt.

So unless the airis exiting under the dash, or at the window (cable/flap issue), I'd suspect that. I assume that the squirrelcage fanis securely attached tothe blower motor !!!