Luke,  it sound like you did it "the usual way."  One just has to
be respectful of the stored energy in those springs.  In my opinion
they're not as dangerous as Victrola or music box motor springs! :)

I have used two methods of recovering sprung bellows.  One is to leave
a strip of the original cloth on, holding the span together.  The other
method is to cover just the open end, and tack it and let the glue set
up, and then insert the spring and continue with gluing down the cloth
(the sides and hinge).  By the way, I like to use a large clamp and
compress the bellows before gluing the hinge to avoid hinge bind.

Of course this is just the way I do it, others may have completely
different ideas!

  Q. Wow many ways are there to cover main bellows?

  A. That depends on how many technicians you ask! :)

David Dewey