Have U attempted to seporate that next flange that couples the pump housing to the motor housing?
Im guessin the impeller is what U R dealing with now.
Hate to sound fussy but how bout another photo.
The snail the impeller take a photo of that. Is it held on the shaft with a small nut? Is the impeller aluminum or metal?
Im pretty confident I know U well enough to say if U cant figure it out its a bit of a jig saw puzzle hu?
Bet U R happy that big black Mack aint this fussy.