i doubt it, the '08 headlight assembly has a different shape on the bottom (rounded) vs the 2005-2007 assembly which is flat on the bottom.....i mean the mounting screws might line up (maybe i dont know) but it wont look right since the '08 also has a matching portion on the front facia that blends with the new headlight assembly. as for the grill i think the 2008's have a taller grill so again i would think it might be a prob doing a swap to a 2005.
2008 Grand Cherokee Limited 4X4, Light Greystone Pearlcoat, Hemi, Tow Group, 18" Chrome Clad Wheels. Original owner, 20,000 miles
2002 Wrangler Sahara, black, 4.0L, 5-speed, Dana 44 rear axle with Trac Loc LSD, duel tan tops, Canyon wheels with Wrangler Silent Armors. 75,000 miles, 2nd owner.