Actual filming locations in "Maynila, Sa Mga Kuko Ng Liwanag"?

I'm not sure if the current location of Ah Tek's place, at the intersection of Ongpin and Misericordia (now Tomas Mapua), is now called "New Sin Chi Sing Trading". I'm more curious about the construction site shown at the beginning of the film. What building is it now, and where is it located? I can't seem to find any info about it.