What should I have it on Summitpost? Leave a comment, I'll change it to whomever has the best argument.
Personally I would go with Signal Peak. It is the name of the highest point and is the more well known of the two. Glenwood Mountain is more for the general mountain area.'
The same thing happens in the House Range in Western Utah. Notch Peak is the highest point on Sawtooth Mountain, Howell Peak is the highest point on Antelope Mountain and Swasey Peak is the highest point on Swasey Mountain. Still, almost everyone (including the SP pages) uses the names Notch Peak, Howell Peak and Swasey Peak over Sawtooth Mountain, Antelope Mountain and Swasey Mountain.
Just my opinion, but I would go with the name Signal Peak.
The GNIS calls it both (effectively) Signal and Glenwood. The coordinates they give are within feet of each other, if off by elevation by 40' or so. Best to mention both. Maybe a separate page for Signal could just indicate going to the Glenwood page?