I ended up replacing the #1 cap with a 1-barb dead-end cap like #2 has. I was so frustrated that this 2-hour job was now into day 2 that I didn't even bother replacing the o-rings. I just pulled the old cap off and threw the new one on because, the way this job has been going for me, I figured I'd have leaks everywhere any way so why bother trying to do things "right" anymore when a simple job is already biting you hard in the ass. Expect more crap and deal with it as it comes.
Well, I had no leaks anywhere.
So now it has all new injector hard lines and deleted the fuel supply hard line.
I have no idea if there is any benefit to all this time and money, but it's done.
I appreciate the input and help from those here.