That depends on what type of heads are on each, and the year it was built.
You need to be more specific on your question, add a little detail to it.
It depends on what heads and ignition system you're using. You'll have better luck with AC plugs in a Chevy.
.060
1-8-4-3-6-5-7-2
Does it turn over? Does it have spark? Does it have fuel? Does it have compression?
Per Champion spark plug applications chart, the gap for 1989 Chevy 305 (5.0L) is .035.
The Spark Plug gap is .045
Take a known good spark plug and connect it to one of the spark plug wires. Ground the plug to the block and watch the gap for spark while someone tries to start the engine.
.045"
.035
.45
.045