MB 59: Musaf - After the Torah is returned to the Aron. In our places, where we return the Torah right after reading it, one shold remove his tifilin after the kadish which is before the Musaf prayer. It is written in the Eliyahu Raba that on Rosh Chodesh one should remove the tifilin after the k'dusha in uva l'tzion, but before the last paragraph of uva l'tzion, "y'hei ratzon milfanecha, etc," and should not wait until after the kadish so as not to create an interuption between kadish & the musaf prayer.
MB 60 : So too on the intermediate days - The later commentators wrote that since there are those who say that one should not put tifilin on at all on Chol Hamo'ed, as will be said in Section 31, one should hurry to remove the tifilin before Hallel, while the person leading the prayers should remove them after Hallel. On Chol Hamo'ed of Sukkos, in which there is an additional wait for the Esrog, even the leader of the prayers should remove his tifilin before Hallel. [the Esrog is one of the four species taken on Sukkos, which are first used immediately before Hallel. I suspect that this was written in a time when an entire synagogue shared one set, so there was quite a wait. --YM] Those who have the custom of wearing tifilin all day should put them back on after musaf on Rosh Chodeh, and he need not make a new blessing if he had it in mind to do this when he removed the tifilin - this according to what the Rama decided above in chapter 12. On Chol Hamo'ed, one should not put them back on all day. Those who put on tifilin according to the opinion of Rabeinu Tam [Rabeinu Tam has a different order to the verses which are written in the tefilin. Some people have a custom of wearing these tefilin after wearing those that follow Rashi's order - although all agree that "Rashi's Tefilin" are correct according to the law.], should should not put them on at all during the intermediate days of a festival. On Rosh Chodesh, they may either put them on after the prayer leader concludes the Musaf prayer, or they should remove Rashi's tefilin before "uva l'tzion" and put on those of Rabeinu Tam during uva l'tzion [and then remove them for the Musaf prayer].
MB 61: "K'dushas keser" - Meaning that at the point in the Musaf prayer where we say "n'kadesh" [the beginning of K'dushah], in a few places that say instead, "keser yitnu l'cha" [let them give _you_ a crown]. If so, it is not right that one should have the crown of tifilin on _himself_ at this time. And [in these congregations,] even during the silent Musaf prayer one should not have his tifilin on. Obviously, one who forgot and started to pray the silent prayer with his tifilin on should not stop and take them off in the middle, because all of this is only a custom.
MB 62: In all places - The Taz writes that if one has the custom not to remove his tifilin for musaf, no complaint is lodged against him - because we do not say the k'dusha of "keser yitnu lecha" [let them give you a crown], and I have heard about one particular Gadol Hador (leader of the generation) that he did not remove his tifilin at musaf. An individual who prays with the congregation certainly should not do differently than the community's custom.