Thank you for the correction flotsamnjetsam.
I did quite a bit of searching, and never came across Bobinghanger. However, after viewing the two pages that you provide links to, and doing an independent search for Bobinghanger, it appears as if he was indeed the tallest player in NFL history.
If anyone were to provide his name in their guess, then they would be the winner. However, if his name isn't produced, then DDD should get the credit for the win, as he had the answer that was originally supplied.