plumbing puzzle

I have an outdoor shower with 1/2" galvanized pipes. I forgot to winterize from the outside handles up to the shower head and it burst at the t-joint. I managed to disassemble it by threading the right side of the 2.5" pipe further into the right side elbow, and loosening it from the left side at the t-joint.

However, it wasn't so simple to reassemble. I thought I could thread both the left and right side 2.5" pipes into the elbows and then back it off into the remaining 4th thread, but threading in to the pipe and then gently unthreading tears up the plumbing tape (and I've tried plumbers puddy) leaving leaks.

I'd hate to tear this all the way down under the Trex decking. Anyone know how to reassemble this plumbing thread puzzle?

If I was doing this job I would take the street 90's out of the valves and run new copper up the same way to the shower head.
If you don't do copper soldering then you could do it in 1/2 pvc piping. There is no way you can put that together without it
leaking. You would need a union and there is no room in your piping.

it was assembled before it was attached to the wall You are going to have to put in a union or change something else