To lock my hood I found a Masterlock bicycle cable lock that has a slider lock that allows you to adjust the length of the cable. I run it up behind the hood latch then down around the grille braces in front of the radiator.
However GMC's allow a bit more room for reaching into the grille, so for your chev you may ned to get more creative. On my '65 Chev I ran a cable down to the frame rail so I could reach the lock behind the bumper.

1956 GMC 370 dump " 'Tater "
1970 VW Volksrod "the Black Bomber"
2007 Chevy Avalanche
2020 Jeep Cherokee Trailhawk,
2005 Harley Davidson FLHTCUI

I dig all cars, old and new, whether they were hammered out of American iron, German steel, or Japanese tin cans. Being unable to appreciate them all is missing out on a world of great things.
But thats just MY opinion! :P