...was just curious if this could be one gauge to show that I was ready
Not in and of itself. But it bodes well, all told.
..was curious if the HR info could give me further confidence that I have chosen the right race pace.
If the run felt easy (like you could've repeated again, if not again and then some), and the pace was relatively fast, and you don't incur any lingering residual effects (as in fatigue), it should help add to the confidence that your other workouts have already built. No single effort is going to tell you you're ready, except that which takes place on race day, or that which matches your goal. It's really more of a build-up among a whole host of workouts that will illicit preparedness.
I suggest in the future, if you're digging the HR thing, to incorporate a simple, repeatable aerobic benchmark type of test. For example: 5 to 15-miles on a interruption-free, repeatable loop (like a 2-3-mile loop close to home) at 80% of MHR or 90% of LT HR [within a 7-8bpm window] while measuring each loop's split, your overall time, average HR, and your overall perceived effort. Take note of the conditions and the shoes you use, the food you ate beforehand and how you tend to recover afterward. Warm-up fully beforehand and limit what variables you can. Such a simple test can reveal a lot, and may even change the way you train.