KZ750H regulator/rectifier

I ordered a reg/rec from Parts-n-more.  On their website they showed a Shindingen part...the one they sent was a Rick's.  That's not the issue though.  The Ricks only has 4 wires in the plug instead of 5 in the one that came off the bike....there is no brown wire...just 3 yellow and a black.  Is this going to work?   It's the one they list for an 82 750H   

I'd say yes.  brown wire is the voltage sensing wire, but the Ricks reg-rec probably has the voltage sensing built into the circuitry. and just to be sure, I'm assuming the ricks unit also has a power wire not routed thru the connector, either: red, white or red/white.

Yes ....there is a power wire.

A 4-wire is generally a better design than the 5 wire, so you could call it an upgrade. The 5-wire system uses the accessories circuit to set the charge voltage which has a big flaw - too much draw on the accessories results in a voltage drop, and the regulator will increase voltage to make up for it. This means you can have 14.2V at your accessories and 15.2V at your battery, which will kill the battery. On these older bikes this can happen just from turning on the headlights on some bikes.