"The first thing I did with McCartney was a bit of mixing on the WILD LIFE album. I was fairly new to engineering at that time and did a mix on a song called I AM YOUR SINGER while no one was there, partly for my own amusement and parly because they wanted some ref copies anyway. They ended up using mine which made me very pleased. I also did some singing on TOMORROW. Remember in the middle eight where it goes ba-ba-ba-ba-ba-ba-ba (chuckle)"
- Alan Parsons, Alan Parsons interview – “The Rise Of Alan Parsons” by Howard Cummings, published on the October 1976 issue of the Recording Engineer/Producer (RE/P) magazine
"And I probably got to know Paul and Linda best on the  ‘Wild Life’ album, which I didn’t engineer; I did a mix on one of the songs on Wings’ ‘Wild Life,’ and Paul said, ‘It’s fine, we’ll go with it.’ "
So that was my first real breakthrough, just getting a mix of the Wings onto that first album. […]
Alan Parsons – From Ultimate-Guitar.Com, July 12, 2020