Never even bothered to take the bread back out, turn on the tap and it will
find it's own way. The only problems I've ever had was getting wood chunks
(from drilling holes) stuck in the cooper pipe after I shove them through
small holes. I know use a shop vacuum to try and suck out such things before
I put the taps on.

Just on note for the newbie.

If you clean the pipe and add enough solder paste you can solder your
fittings upside down, most people tend to think that they need gravity. I
fit everything together and then solder it in place, I usually keep a wet
towel around to cool down joints if I need too.