Installing 68 hood on 71 GMC

[49studebaker]

My question is just the opposite of mickymouse. I removed the dual headlight mounts off of my 71 GMC radiator support and plan on installing a 68 Chevy hood and grill. Currently the fenders are about 3/4" wider (large gap)than the 68 hood. Are rad supports the same on both trucks, or is the 68 narrower? I know the hood on a 68 is narrower on the front due to the fact the GMC had a shorter hood with the top bar adding to the length. I'm currently on crutches so all I can do at this point is "wonder" if I just need to re-adjust my fenders or replace the radiator support. Any ever do this before or know if it'll work? Thanks for any info.