Matchbo is on the 2nd floor right above the very good Jiro-like Menya BonTen on Dogenzaka in Shibuya. It's a fairly cramped store so watch your step on the way up and watch your head inside the place. They served a good tsukemen with 4 slices of excellent coarsely-cut melt-in-your-mouth pork (I recommend it without the nori strips though). The noodles were thin, regular garden variety but the very strongly-flavored and slightly thick shoyu broth with a thick layer of oil floating on top more than made up for it. This is one of the cases where I wish the noodles were a bit more matched to the broth, a thicker noodle with a rougher texture probably would a stood up a bit better to the broth. Based on the quality of the pork and the broth and the proximity to Shibuya station I can say that this place is recommended. A bit expensive for the volume you get though, 1000 yen. However there was no line at 6 PM on a Thursday. In addition to BonTen there are other ramen shops on the third and fourth floors I believe.
Gourmet Navi page
Diddlefinger Map (English labels)