Yeah turned into a complete strip down,
I nearly have a new mower now.
I'd already replace the right cutter bearing housing as it was broken when I purchased it, and did the bearings at the same time.
But on closer inspection I've found the clutch had been reamed out like yours in your video deejay. So I've ordered that along with the clutch bearing, then when I took off my self aligning bearing housing off I found my bearing nearly fell apart in my hands.
As far as I could tell the only bearings left were the drum bearing and I think they are still ok. They still spun smooth, so i just packed em with grease and put them back in.

Its all painted up like new now, just waiting for my blades to get back from the sharpener, my new clutch and bearings and my decals in the mail.
I've taken loads of photos to upload when i'm done.
The only decal i'm not sure of deejay is the one that goes on the front of the catcher.
Its the model 450520 which I think is the same as yours, do you have a uploaded photo of your catcher?
Thanks
Matt