The Rambam has an entirely different approach in this matter. He holds that according to Rebbe who opines that the lamps were positioned from east to west, the
neir ma'aravi - the western lamp - was the westernmost lamp. i.e. the lamp closest to the
Parochet and Holy of Holies, and it was the first one to be lit.
In addition, the Rambam opines that according to Rebbe's opinion that the Menorah was positioned from east to west the flames on the wicks of all seven lamps were facing the west, towards the Holy of Holies. Thus, "el mul penei haMenorah" does not mean that the lights were facing the lamp on top of the central shaft, but that they were all facing the Holy of Holies which was penei haMenorah - in front of the Menorah.
Accordingly, this fits very well with the words "Towards the penei haMenorah shall the seven lamp lights illuminate (Bamidbar 8:2), since all seven lamps were facing to the direction (westward) which was in front of the Menorah, i.e. the Holy of Holies.
The Rambam is not concerned about the fact that when the Kohen enters and goes to the end of the Menorah to light it, he is passing over a mitzvah, since the Torah insisted "lifnei Hashem" - that the candle to be lit first should be the one which is closest to Hashem. Thus, the mitzvah is to kindle first the lamp most west, and the mitzvah to light the others commences only after this one is kindled.
Another novelty of the Rambam is his opinion that the Menorah was lit twice a day, in the evening and again in the morning. According to his view, we are commanded that all seven lights should burn continuously, day and night. Therefore, if the lamps are found still burning in the morning, they are attended to and allowed to continue burning. If they are found extinguished, they are cleaned out; that is, the wick and remaining oil are removed, the lamp is wiped clean, a new wick and new oil are put in, and the light is immediately lit; for Rambam (Temidim U'musafim 3:11) holds that "hadlakat haneirot hi hatavatam" - "The lighting of the lamps is what is called readying them," i.e., "lighting" and "readying" are the same act.