Underside of the 38" mower deck
At some point the mower had hit something hard enough to bend the
forward edge of the deck in (towards the rear) about an inch. There
would have still been clearance for the blades but for a fairing to
guide the mown grass to the outlet. I fiddled with it for a bit, but
brute force was the only real option - a 3 lb sledge eventually did the
trick. Then I used the wire welder to put a tack on the joint between
the forward edge and side edge of the deck - the bead there being
broken as well.