Question: How can the non-plot version of changecoords be executed within this procedure?

The changecoords command in the procedure below executes the plots:-changecoords command despite the preceding unwith(plots) command.

How can I execute the non-plot version of the changecoords command in the procedure. It would be very inconvenient of all the various commented plot commands had to be preceded by plots:-

restart; with(plots):   # first command in the worksheet

  # many statements executing various plot commands

 
P := proc()

unwith(plots):

changecoords([x, y, z], [x, y, z], spherical):

with(plots):

end proc:

P();
Error, (in plots/changecoords) changecoords does not accept plot options or other additional arguments
 

  # many more statements executing various plot commands

 # last command in the worksheet