By this, I mean how does the machinery know to insert your target gene (which has been cloned onto a viral plasmid) into the virus particle? Does anyone have any good resources on this topic?
Upon transfection of the producer cells, there are several elements in the transfer plasmid (plasmid that encodes your gene of interest) allowing the packaging of RNA into the viral particles. Those elements are the LTR, but also the packaging signal that drives encapsidation of the produced RNAs (containing your gene of interest) into the pseudotyped viral particles.