I want to know if you can swap out an 88' gmc sierra grill for a 90's model or even possibly a 99' model would be awesome. im sure you can with some custom mounts or brackets but unsure about radiator clearance and lighting situation. just wondering if anyone has tried this?

 

you can swap them they wont require any custom fab work
but the only difference is the headlight style
i had a grill from a 94 on my 88 and it fit just like a glove
the 99 you may want to make sure its the same style that looks like the 88-98 body style or it wont fit

 

They changed a few things through the years. 88 & 89 are the same, 90-93 changed the headlights to single instead of the duals like you have on your 88, 94-99 changed the lower filler panel under the grill and the side fillers that connect to that. So you can bolt up a 99 OBS but will need 2 headlights, harnesses w/ sockets for those lights, the 3 piece lower filler panel under the grill, and the grill itself.