Looking for a billet breather for my 496 oil fill tube.....any have a link?

Wayne:

Go to www.knfilters.com/vent.htm and look up the crankcase vent filter part #62-1519. Drill a 3/4" hole into the plastic oil fill cap and cement this vent filter into the top of the cap and re-install the cap as usual.

Best Regards,
Ray @ Raylar

Is there a benefit to installing this breather and if so, what is it?

Higher horsepower engine versions for certain stock engines will create more crankcase pressures sometimes to a point where the stock PCV system can not quite keep up and a little extra venting of the crankcase can help eliminate the crankcase pressures and keep the pressures from pushing oil laden vapors out past seals and dipsticks, etc.
If the engine is experiencing to much leaking cylinder pressure then these crankcase pressures can become excessive from leakage past rings , etc and they can only usually be corrected with better cylinder sealing from new rings, etc.
Remember the stockMerc 496 375-425HP engines do not create as much cylinder pressures as the Raylar HO600 and sometimes the stock PCV system has a hard time keeping up with pressures and vapors.

Best Regards,
Ray @ Raylar