Sidney mentions that he was classified 4-F, meaning that he was incapable of serving in the US military for medical or psychological unfitness. In reality, Woody Allen himself was classified 4-F.
Sidney tells the barber that he wants his thinning hair cut like that of 1950s idol James Dean. Later on, his wife Kay tells him that he resembles the character actor Franklin Pangborn or maybe Elisha Cook Jr.. Even later, Carol tells him that he resembles Percy Helton.