The Y-Carriage is the carriage that should give you the least problems of the three. Mounting the parts is really straightforward.
I only had one small issue.
Since I use allan bolts instead of the (lower) normal hex-bolts to assemble the Reprap, the angled ones in picture 13 needed to have the washers removed in order not to bump into the studs of the supporting frame.
Y-Carriage 01
Y-Carriage 02
Y-Carriage 03
Y-Carriage 04
Y-Carriage 05
Y-Carriage 06
Y-Carriage 07
Y-Carriage 08
Y-Carriage 09
Y-Carriage 10
Y-Carriage 11
Y-Carriage 12
Y-Carriage 13
Y-Carriage 14
Y-Carriage 15