Is there a guide to buying transmissions?

So I'm looking at purchasing a new engine, only thing is it comes with an automatic transmission but my truck is a manual, so I need to buy a new transmission. And to accommodate this new engine I would need a transmission rated for higher horsepower anyways. The engine in question is a supercharged 5.4L V8 from a Ford Lightning with about 360HP. What I was wondering, is there a set in stone guide for what transmission to use for what HP, or is it more up to how you want your truck to drive? I would also take any suggestions for transmissions you all have.

You are stupid and this question is obviously fake, and it shows your sheer lack of understanding of automobiles.

Talk to transmission professionals in your area. You are looking at a very expensive job here.

Always shop around for the best price when it comes to transmission work. The difference could be hundreds of dollars. And since you will never know the quality of the workmanship or materials they use, make sure to get a good warranty. 12 months or 12,000 miles at least.

TCI TRANSMISSIONS.COM