Bill was actually the second to fly under the arches. The German he was chasing with his P-51C did it first.
WWII Veteran Aviator Bill Overstreet and His P-51 Mustang, Berlin Express
http://www.warbirdsnews.com/warbird-articles/wwii-veteran-aviator-bill-overstreet-p-51-mustang-berlin-express.html
JULY 31, 2013
Good grief, he survived some really close calls. Apparently he was blessed with an abundance of luck, skill and God's protection. What an aviator!!
Good point. But he was the only one to do it and survive, thanks to shooting the 1st guy down.