Gday surferboy
not too sure if fe/c's are the same, but you should be able to adapt this setup
from a wreckers - you'll need a complete L300 cable (from pedal to carby) which will be shortened to suit - when fitted
its a bit hard to say without seeing your carby (pic) - to see whats in place already, but...
1st you'll need an inner cable holder - attaches throttle lever(carby) to inner cable
2nd youll need an outer cable holder - holds outer cable to a fixed point, usually a bracket etc attached to carby base (see pics)
3rd youll need a return spring or 2, & maybe a balljoint (see pic of my twin setup)
you can source the above parts thru stockists of speco & or redline carby bits
dont know if you can do away with the guide bit?, as it acts as a fixed point for the pedal end
dont know about unexpected problems, relitively basic setup - but you may need to extend pedal lever to gain full throttle

make sure when you source your throttle cable its not freyed, kinked etc & moves freely
some extra good info here:
http://www.fbekholden.com/forum/viewtopic.php?t=6385
good easy setup for those long roadtrips surferboy

& like you said, "shouldnt be a problem"
cheers ray