Concerning double pinks...

So, according to the Munson plan, Rocky is ready to move up to two pinkies every four to five days. Saturday will be his first time getting two.
Do I feed him the second one immediately after the first one, or is there a period of time that I should wait between pinkies?

You can put both in and let him eat them at his leisure, if he will do that. If he tong feeds, you can wait for him to finish the first one, then offer the second one.

Once the first one is swallowed, they are usually ready for the second one.

I use the day old pinkies when I feed double pinks, to prevent regurges from too big of jump in prey volume.

Thanks. He isn't tong fed, so I'll just dump them both in at once. I've been buying the pre-frozen ones from Petco and the bag says approx. 1.5 grams. Is that okay? The Munson plan says 2-3 grams each, but since these are what he's been getting, I figured two of the same would be best.

if the munson plan says feed 2 @ 2 to 3 grams ea. = 4 to 6 grams total.

And you are feeding 1.5 gram pinkies x 2 = 3 grams total.

You may be a tad bit short by weight. It's probably not a big deal, there are several remedies.......

1). Feed 3 instead of 2. (3 x 1.5 = 4.5 total), or
2.) Feed on 4 day intervals instead of 5, or
3). Try to find heavier pinkies, or
4). Just feed like you mentioned above and settle for a slightly slower growing snake.

I usually make sure their first food item is most of the way to their stomach before offering the second, but I do tong feed. I don't want to stress them too much and cause them to regurge (I've had it happen with this). As for following the Munson plan, I don't...so you'll have to rely on others for advice on that.