Throwing a bunch of codes is often bad battery or bad grounds. With the motor being swapped I'd look close at what ground connections should be clean and in place and didn't get lost during the swap out. There' s a few good diagrams on it here, I know the search function on here sucks, better to use google.
copy/paste this into google
site:camaro5.com engine ground connections
https://www.camaro5.com/forums/showthread.php?t=221700
https://www.camaro5.com/forums/showt...=399658&page=4
https://www.camaro5.com/forums/showthread.php?t=511228
I'm thinking along the lines of the post that is above me, before I finished searching to post this.
Checking grounds and general cable plug-ins to make sure pins aren't pushed back or bent or a cable got mashed during the work. I'd do that first before trying to chase a single trouble code only, because of how many you got at once.