I need more data to have a chance of decoding it. Maybe get me photos of the plates and we'll see if it can be ruled oit or not. WM80 is a Holden ute in HX, which is what the XU3 and XX7 Sandman packages were based upon. XX7's are relatively easy to get a handle on but XU3's in a HX ute are all but impossible. You might be lucky.