I have never shot a Gator but have shot a fair few Crocs & I think a 270 is too light , more so with
130Gr slugs , better with a 30/06 min with 180's , Barnes or Swift A frame and up .

I must say how ever that a 9 footer is a pussy compared to a 12 footer where things start to get serious , even a 10 footer is far more substantial than only a foot shorter but many pounds lighter 9 footer !

I have had a 400Gr soft @ over 2000fps only crack the skull of a 14.5 footer & stun him not kill him out right , very surprising , the cracking going right into the brain pan !

See if any of these help .