There is a video of a guy using what he calls 'The Swoop'
when he backs up. I tried it and it works.
Basically you aim your truck into the spot headfirst, then at the last moment pull it hard out of the spot. Pull up, you are at the right angle, back in slowly. I put a traffic cone back there to tell me I'm back far enough.
FWIW... I tried having my wife assist, wanted to kill each other.
NOW... I have her go sit at the picnic table till I'm parked.
No shouting back and forth, no miscommunications...
She's still speaking to me. Married 39 yrs now...