Listed under your hood on a sticker.
According to Champion spark plug applications chart, the correct gap for 1995 Chevy Tahoe 350 engine is .035
.040 for best results
0.040 inch
.060 inch
65
firing order is: 1,8,4,3,6,5,7,2
If you have spark to the spark plug, the fuel injector may be at fault.
gap .060 good luck
Mine is out of a 02 Tahoe it is 0.060 in
0.40
.060
.43 is the gap