With 1090 muscle and 44 ml, the mutant I just fought had 1044 defense, but I wasn't paying close attention to the other stats.
With 1057 muscle, 1097 moxie and 67 ml, the mutant had 800 hp, 1067 attack and 1067 defense, so it caps both at 1000 (and hps are 3/4ths of defense as usual).