I haven't done any darkroom work in about 40 years, instead sending everything to the lab, so my memories of using an enlarger are very weak. As for assembling one that has all the parts wrapped up and packed in a box, I have no memory, as I have never seen the insides of an enlarger.
Anyway, I have just been offered a photocopy of the manual for an early Leitz Focomat condenser enlarger that looks very similar in construction to this Telesar (which might be a copy of the Leitz), so maybe it will help me to get all the parts in the right places when I assemble it.
And, as you said, if it's not all there or it doesn't work for me, I will just get another one . . definately one that is a little more of a mainstream marque rather than this off-brand model.