Overheating issue.

Why did you add stopleak with a brand new inframe? Likely you've already gummed up your thermostats

 

In my opinion stop leak is a last resort get you home fix and it does not always flush out. Seasons are changing and your problem could be unrelated to everything you thank of because it was a preexisting condition. My radiator man told me, 25 or 30 years ago, a bad radiator will cause the engine to run hotter the faster you go.
Dirt build up on the air side of the cores and or between the a/c, air to air, and radiator can do the same thing. Some times that is impossible to see from the outside looking in. If the engine is running hot, the radiator inlet is hot while it's outlet is cold, it is a bad radiator. Just some thoughts and maybe use the search block, top right of your screen, to broaden your thanking. Would like to know what you find or hear other questions.
Don't settle for half fixed because if it is inframe related and runs long enough to get off warranty it is on you.

 

If its a hose collapsing, you should be able to see it if you rev your engine up at the engine and watch the hoses.

 

Remove the condenser and the CAC and use a blow gun on the (dry) radiator to blow the dirt out of the core. You will be amazed how much dirt comes out.

Rinsing it with water does not work (ask me how I know). It only turns the dirt into concrete and plugs it up worse.

I chased this very problem on a Pete with a Cat and, unsucessfully, threw all kinds of parts at it. Blowing out the core solved it.