Can you put a 1986 Chevy truck front clip on 1979 truck?

No, you can't directly bolt on a 1986 Chevy truck front clip onto a 1979 Chevy truck. The body styles are significantly different. While some parts *might* be adaptable with extensive custom fabrication, it's not a straightforward swap. The fenders, hood, grille, and core support are all different shapes and sizes. You'd be looking at a major body modification project, not a simple bolt-on swap.