I am about to reconstruct my heater box with the new blower motor however I have attempted to clean out the fins with some success however a large amount of presumably dirt and gunk remains. I have tried degreaser/water/compressed air
and carefully using a thin blade screwdriver to dislodged some of it.
this is what remains.
Does anyones got any tips of what could dislodge this crap as I don't particularly want to inhale this stuff when its reassembled.
Cheers