There isnt one specific spot that I use for this shot since the El runs right through Fishtown, but typically I shoot between Master and Palmer right on Front Street there due to other factors like wedding day logistics or engagement locations.  Its another one that involves a little bit of time and effort especially if we involve your entire wedding party as well, due to the traffic going by, but its a fun shot and definitely checks off at least two boxes.  Unique and Philly.