Where to put the gene after eukaryotic promoter for best expression levels?
I used pEYFP-N1 (stock vector) where the spacing between the CMV promoter and the EYFP start codon is ~88 nt, and the expression is high.

I also cloned a protein 5' of the EYFP, only 4 nt after the CMV promoter. The expression of this fusion was also high. Because I was only using the chimeric protein in experiments, I did not try to assess differences in EYFP expression.

If you look here: https://synbiota.com/projects/19/sequences you'll see the basic pEYFP-N1 vector and the separation between the CMV promoter and the EYFP coding sequence. 

On wiki: "The TATA element and BRE typically are located close to the transcriptional start site (typically within 30 to 40 base pairs)."