adarvasi;
I just released the spring from my training carb (which is also a front carb, so no mirror image direction change!), and the spring-end rotated a full 180Deg plus, clockwise (with authority!**) to the area shown here in green (while other end was still in position on Choke linkage),
...so I believe it is still a preload issue...while keeping one end in Choke linkage, try winding other end CCW until you can hook it over notch in housing...yes, that is a fair amount of preload force! Constructing a hooking loop from a piece of wire with which to pull the end around may help...that's how I'll do it!
** now I need to rehook it also!
Good Hunting!