Now I need overflow help

[AndyL]

Quietest overflow by far, is I believe refered to as the SOS standpipe system.

Basically you use a pair of bulkheads, one as a primary overflow - one adds a proper gate valve (the ones sold in calgary as gate valves aren't, they're knife valves - gate valve should have a knob and threads to allow fine tuning) or if you're willing to fiddle a lot, a ball valve. The purpose of the ball valve is to throttle back the flow so that the overflow only removes as much as the pump adds. The second bulkhead gets a stand pipe, to an emergency overflow level - if water hits there, it exits via a completely open run of plumbing to your sump, no overflow, lots of noise, you can't mistake the fact that you need to have a look at what's causing the blockage in the primary return.