Many shuls have menorot at the front of the shul on either side of the aron. I understand that basically this is a zecher l'mikdash. However, is there a source for the minhag to place specifically two menorot? The first Beit Hamikdash only had one menorah, and the second Beit Hamikdash had 11 I think. An additional difference from the Beit Hamikdash is that many shuls have menorot that do not have 7 branches (either more or less) and have a decorative center piece rather than a shamash. Also, some shuls have these menorot attahed to the railing around the bimah. So are these just stylistic choices of the architect or is that a source somewhere?
Update: A friend of mine suggested that the two menorot might be sourced in the two olive trees in Zechariah 4:3. I wonder if there are any sources in sifrei Chazal or books of minhagim that make this connection. I would love if someone has a source about this.