Don't try to overinflate your instrument time. Use the most conservative number that adequately represents your experience. It looks funny if you have 1200TT and 500 Actual. Nobody is going to buy it, and it will really show when you go to do the sim ride and subsequent simulator training if you get hired. If you meet the requirements that they have for the instrument time you need to be called for the interview, then you have enough. Everything else is excess. You can't go wrong here using a conservative number.