Syncro 4&4 Discussion and Q&A last answered over 2 years ago.
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They all have Syncro on the front pannel above the left hand headlamp, in Black, grey or silver. Most have a matching "4WD" stickers on the front doors aswell but some have full length "syncro 4x4" decals along the sills instead, must have been an option or something. On the back they tend to have a fading "4x4x4x4x4" sticker on the far right of the rased bit of the tailgate, above the syncro badge; again not all do though.
All but the big syncro 4x4 stickers are avalable from Brickwerks or syncrospares. The sill stickers were on ebay from america a while ago but I'm not sure now. Doubtless Baxter will be able to copy them if he has/gets the plans. Probubly not that cheep though due to size.