Last time I caught big crappie that size was from Lake San Antonio on the CA coat just outside Paso Robles.
The lake was very, very low at that time.
Just tossing a white curly tail with a 16th oz. lead head was producing a fish on almost every cast, with my biggest at that time topping 3 lbs.
I'd be interested in how you do if you choose to go. I doubt I could get there from Eugene, over the hump due to snow to try, even if I could afford the diesel fuel for my truck to go.