I was wondering if it's possible to upgrade the 85 GSL front brakes to the 84-85 GSL-SE ones by simply swapping out the rotors and calipers. Is it this easy or do I have to change the spindels and other things as well?

 

spindles are the same, just use the SE's mounting bracket for the caliper.
your going to be changing your bolt pattern in the process.

 

Cool, thanks for the help.