I developped a Google Sheets workbook that generates the S&P 500 members dating back to 2010, using the information provided by Wikipedia (see link). I'm using a slightly modified version of the sample Dropbox Universe Selection template provided here. In this sample backtest, I'm using LINQ in the On Data section to simply select the top 10 most expensive securities from the S&P 500 and buy/rebalance equal portions of each.

On the Info worksheet of the Google doc, the links to automatically download the CSVs are provided. You need to copy in the worksheet ID (from the URL) of your own version of the Google doc or the links will be incorrect.

Make sure you enter your backtest start date on the Info sheet of the Google doc or your backtest will most likely start will blank data for the first few months.

Note: There is definitely a couple discrepancies in the data. For example, Wikipedia tells us DLPH was added to the Index on December 21, 2012, and does not provide a date where it was removed. However, DLPH does not show up on the active members list. Overall, it's very close to the 500, and the error is always less than 5. I put a graph on the Info worksheet that tells you how many companies are tracked at each point of time, to give you an idea of you big/small the error is. The most recent count is 505, which is correct.

The spreadsheet can be found at this link. I recommend copying it to your own drive, and updating the worksheet ID.