In Chapter 6 of The Great Gatsby, how truthful was Gatsby when he relayed the story of his life to Nick?

It is clear that Gatsby's tale of rags-to-riches has a
certain fairy-tale element to it, and it certainly is hopelessly Romantic. It reports
how Gatsby has transformed himself from a humble Midwestern boy to an East Coast
celebrity. He, however, has also transformed Daisy Fay, within his own imagination, from
a Southern girl to an ideal of radiant beauty. The novel is packed with
references to magic and to enchantment, and, at least within the confines of his own
mind, "The Great Gatsby" is an accomplished magician. This title carries a suggestion
of the showmanship of stage magicians, who practise an art of illusion and use such
names to advertise their performances.

So, it appears to me
that there is a profound ambivalence in Fitzgerald's attitude to the imagination. It can
be seen to work magic and make ordinary life seem enchanted; or it can be seen to
generate illusions that keep harsh realities out of focus and help perpetuate
injustices. Therefore when we think about Gatsby's autobiography as he relays it to
Nick, we are perhaps slightly sceptical of the Romantic tinge that he gives his
transformation - a scepticism that the rest of the novel bears
out.