Semi-Spoiler since I am revealing something very funny.
I remember the lines sort of but can't find a clip, no idea of episode or season:
The computer asks Lister something to the effect, "How would you like me to create a woman, completely indistinguishable in every respect from the real thing?"
Lister is thrilled by the idea and tells Holly he would like that very much, why not do so?
And Holly says, "Because I have no idea whatsoever of how to do this; I couldn't even do the nose."
I found that particular exchange as funny as any science fiction humor I have encountered although I understand that Holly makes up a lot of stuff to tease Lister.
Does anyone know the episode or have a link to a clip?