I can see that working out pretty good. I've done something similar before, but I didn't bolt my classifier on. It's works really good , but avoid putting oversized boulders in, try and wash those down first in a bin or bucket. Good idea, I say roll with it. I would brace where ever you bolt the classifier onto the sluice with some heavy gauge 1" Al bars to protect your sluice from cracking. Post pics when done, I'm curious to see what you come up with.