90 degrees or 45 degrees? US or Europe?

Typically the contact point will be at a 90 degree angle in relation
to the front spring. This will ensure that there is optimal
surface area between them, and provide for good conductive
contact. The contact point does not have to be at 90 degrees,
and this is where the tuning will come into play. Each artist likes
to set up their machines differently. The rule of thumb, for a nonadjustable
binding post, is to always put the machine’s contact
point at the 90 degree angle against the front spring. This is
usually how the machine’s frame designer envisioned the machine
working. This will not work in theory if the front and rear
spring lengths have been modified from the original setup.