Right there in bold mate. Y61 is the common name for the Patrol produced after the Y60, us Aussies call it a GU model Patrol, in other countries it might be a Y61 Safari. Same, same. First released is the series 1, every two years or so Nissan release a new variant of that model with slight changes and upgrades, but they remain relatively the same. The first GU/ Y61 was released late 1997 and this shape went up to the series 3, or GUIII, around 2004 (i think). Then the series 4 came along (GUIV) see pic below, early GUII on left and the body change of the GUIV on right, the main cosmetic differences were the headlights (from headlight and indicator being separate to now being as one), flares on the guards are larger, larger tail lights and dash board changes. There is many other things but those are the main things. The new design Y61 GUIV went on until GU8 or 9? Then came along the Series 1 Y62...
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