I hiked up Grays and Torreys on July 11, 2001 and I did Grays again on August 19, 2005. Both times I started at the Stevens Gulch Trailhead.
To get to this trailhead take Exit 221 off Interstate 70 at Bakerville. On the south side of the highway there is a sign for Grays Peak and follow the dirt road and signs for Grays Peak for about 3 miles until you get to the parking lot and well marked trailhead.
The trail up is pretty easy to follow, for there is a well defined path all the way up Grays. From the top of Grays, head north and down the connecting saddle and then up Torreys, while there is a slight trail, it basically is straight up to the summit. There are no false summits on either of these peaks.
To return to the trailhead, come back down Torreys the way you went up, but at the bottom of the saddle, transverse the eastern side of Grays to the trail you headed up originally.
Both times I have been up on the saddle, there is a snow field that you will need to cross. While the snow field was not too difficult cross, it might be a little slick in places. There should be a path leading out over the snow field.
The distance to the summit of Grays is about 4 miles. Crossing over from Grays to Torreys is about another half mile, and about another half from the summit of Torreys back to the trail up to Grays. The round trip distance is about 8 1/2 miles.