Based on hearing the track I have concluded:
"Marcella Hey" is Carl
"Heyyy Marcella" is Brian I think...
"Doo be doos" is Al.
"One arm over my shoulder" (not the melody but the part above, answering Mike's melody) is Blondie or Ricky... not sure..
I've always thought that last part was Dennis...and I also hear him, or someone like him, on another part...
Here's some track info from the console strips:
11 - ONE ARM first chorus
12 - ONE ARM 2nd chorus
13 - Mike Du Be Du Be Du Be
15 - Al extra
16 - Mike and Al
17 - Carl and Jack
Oops...I left out a part from the same console strip:
7 - tag MARCELLA
That could be any of them...