I am building a Prusa i3 Rework, and I haven't been able to find out how to attach my J-Head extruder (see below), at the moment it's just kind of held there by pressure, but it seems there are two holes on ether side of it; not sure if they're meant to hold it in place, but it seems that way.
Any suggestions as to what I should use to hold it in place? This is definitely a part that gets moved around alot.
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