It’s a bit hard to see. The tray looks like it tappers very close to the bottom of the dump at the last spot that is hitting.
I reckon that sump is just wrong. Did they know it was going on a stroker? I have a photo of a VN Group A sump. The windage tray is flat across the sump. I don’t know if they had enough clearance for a stroker and you would never find one anyway, even if did fit HQ-WB.
I have a book called the Holden V8 Engine Manual by Larry O’Toole. They cover strokers and give a lot of detail. I will quote what they say about sumps; “Windage trays and crank scrapers are not considered necessary on these engines as they will usually see mainly street duty”. I reckon unless you can find a windage tray sump with enough clearance, you would get away with the standard one. Unless you are going to really get in to it I guess. I would be scared of dramas if you cut and shut the one you have.
But I am sure there are more knowledgeable on the subject than me.

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The windage tray on the group A doesn’t go as far along as the one you have to. I wish I could put a photo of it up.
You would nearly need to shorten that tray back by a third to get clearance at the far end by the looks. It looks like you need to bash a dent right through to the bottom of the sump that you could see from the other side.