I'm not familiar with Florida climate other than the teasing I get from in-laws that live there when they try to get me to visit. I'm assuming it is warmer than New Jersey.
How old are these pullets? If they are still peeps I think someone else could give you temperatures needed. They need to be old enough and feathered enough to handle whatever temperatures you have there. Here I start introductions at about 5 weeks but you might be able to start a bit younger.
Once my pullets are acclimated to my climate I start by putting the dog cage in the chicken run near the chickens feeding area which is under cover to prevent rain getting in their feed. I put a piece of plywood on top of the cage to keep the adults from sitting on top and pooping on them through the wire. Inside I put bedding, I hang a small feeder of start and grow in the front end right corner, and a small waterer in the left front corner sitting up on 4 bricks, 2 on top of 2, to prevent them scratching bedding into the water. At night I cover the entire cage with a tarp to prevent drafts and because they will cry until they are covered and in the dark.The pullets go inside and stay there for at least 2 weeks, longer if very small. The adults and the pullets can see each other up close, see but not touch. I give daily treats right along the edge of the cage inside and out so they are forced to eat very close together and relate the strangers to something good. After 2 or 3 weeks of this be prepared to spend a few hours in the run with them monitoring as you let the pullets out to mingle. Be prepared to return them to the cage if things go south. Expect a bit of pecking and chasing as is normal in the pecking order. Some things to have in place to keep problems at a minimum can be additional feeders and waterers in the run to prevent territorial clashes, some places for the pullets to hide but not get trapped (needs 2 ways in or out like a tunnel or firmly propped up board), distractions like hanging a cabbage or 2. If all goes well then yay! If not then pop the pullets back into the cage for another week and try again.
I'm guessing you don't have a brooder in your coop. There are ways to introduce very small chicks by building the separate brooder and run inside the coop using tiny doors so they have a way to escape.
@aart or
@Texas Kiki or several others can help with that.
Please ask lots of questions about anything you don't understand. My answer may not work for your set up so some pictures of coop, run, cage, pullets can always help us see where your going with this.
