I've got a Garmin E-Trex Vista with a RAM mount that fits to a dirtbike or quad handlebar, and temporarily modified it to fit my stock Teryx cage...One of the better handhelds at the time. Works great! Now there are alot more so look on the internet under handheld gps. Now I just got the Lowrance BAJA 540c for my B-Day! Can't wait to mount that bad boy!!
I have the Garmin 60CSX and really like it. Reception is great. Only thing is the screen is a bit dim under alot of sunlight. Is your cage stock or aftermarket? I have an aftermarket cage that has a crossbar above the hood. I put mine their using a large diameter rail mount from Garmin and it fits perfect and I can see it without taking my eyes away from the trail. Can also plug it into the power outlet from that location very easily. I think Rutcutter was able to mount his using a hard mount scewed into the center console. Here is the thread:
I have used the plain yellow Garmin E-Trex for several years and it has held up to alot of abuse. Things like falling off the mount on my quad and riding for god knows how long with it dangling from the wrist strap, dropped on pavement, left in hot cars and many more....It's cheap and simple.