Water temperatures and volumes for rests

So I'm brewing a wit. I've been brewing quite a while, but have never done protein rests. I still use a cooler tun so it's a PITA to adjust the temperature after dough in.

5 gal batch, 5.5 pre-boil

1.25 qt/lb for a ten pound bill = 3.125 gal mash in
So do I just divide that by 4 and do <3 gals per step in the schedule? And if so, how do I figure out the temperatures for each step?

The schedule is:

5 min. at 113
35 min. at 144
20 min. at 154
mash out at 165

I've been trying my hand at different calculators and am completely lost. Can anyone lend me a hand figuring this out?

Use an online rest calculator. It can figure out what volume and temp water to add to achieve each step