A clean, uncompressed ISO should be exactly 1.36 GB (or approximately 1.46 GB depending on the filesystem).
Use a tool like Floating IPS (Flips) to apply the patch to your Melee ISO. Download and install Flips, then: melee iso ntsc 102 install
Ensure your GameCube can play NTSC games. Region-free GameCubes or those with region-free modifications can play any region's games. A clean, uncompressed ISO should be exactly 1