This is likely your problem. SR is an awful brand and it wouldn't surprise me at all if their TB is causing this issue. The BBK is superior to SR any day. You only have an Edelbrock intake and long tubes as engine mods so the 75mm TB is probably way overkill imo and is also possibly why you're having this issue. Stock TB size is only 58mm so a 65mm would have probably been perfect for your application. You're essentially overcarbing the engine with air. Krem12 would be better qualified to weigh in on that though.
Throttle Body Size Guide | Factory Mustangs - LMR.com
Check the CAI for any gaps or around the MAF. Though usually it does, sometimes cleaning the IAC doesn't fix it and replacement is necessary.
