On Sun, 23 Dec 2012 14:11:09 -0600, G. Morgan wrote:

I tried to remove the old spring from the stationary and winding cones
It's not easy ... I failed

They use a high pressure crimping machine to attach the winding cone at
the factory. The spring and cone are always sold as a unit.

When I was looking at Dan Musick's DDM Garage Door web site, his charts
showed you'd save about 10 bucks or so by requesting springs sans cones.

10 bucks on a $30 spring is an appreciable percentage of the overall cost.

His site even shows how to unwind and re-wind the springs off and on the cones.
http://ddmgaragedoors.com/diy-instru...eplacement.php

REMOVE STATIONARY CONE:
a. Install bolts & nuts from the spring anchor bracket in the stationary cone
b. Next, grip both nuts in a vise.
c. Hook the end of the spring wire with a pipe wrench or large channel locks,
d. Turn the wrench until the spring comes off the cone.
If you do not have a vise, position the spring on the floor
and place a winding bar between the bolts. Hook the end of the spring wire
with the pipe wrench, and lift up on the winding bar while pushing down on
the end of the wrench. Repeat this process until the cone is loose.

REMOVE WINDING CONE:
a. To remove the winding cone secure the cone in the vise,
b. hook the end of the wire and
c. turn the wire off the cone in the same manner.
If you do not have a vise, use the same procedure above, with the only
difference being that you will insert the bar into the winding cone.

However, having tried it briefly (with just vise & wrench), I see now why
most would say it just isn't worth the trouble - so I heartily recommend
buying springs with the winding and stationary cones factory installed.