I dont know if anyone has mentioned it yet, but if your going to the GM route, why not get a front clip from a S-10? It a lil narrower than a Gamaro and I had a friend of mine do it with a 51 Ford sedan so a Merc should be the same thing.
Yeah, and don't go choppin' it either, Henry wanted a gentleman to be able to wear a hat in the car. All this changin' things on cars, it's just not right.
I went the camaro route check it out here..... http://www.jalopyjournal.com/forum/showthread.php?t=229300 ETHER