My wife and I have added speech boards to three rigs, and it was simple and
easy. It was just a matter of determining where they go and plugging them
into the correct socket, making sure they are plugged in all the way. You
can usually tell when they are fully plugged into the socket because they
usually make a snap sound and you can feel it through your fingers. We also
added the 12/10 meter expansion board to my ALS-600, and it was also very
simple and easy. The most tedious part is taking all of the screws out of
the cases. 

However, installing something that must be soldered to the circuit board is
an entirely different issue. I've done quite a bit of soldering and building
over the years, both entirely homebrew gear and kits, but adding a component
that requires soldering it to the PC board of one of these commercially
built rigs, with the extremely tight quarters in which to work, is entirely
too risky for me. I wouldn't touch it! <pun intended!>  

I have a good friend who is fully sighted and who has considerable
experience working on equipment, trouble-shooting, repairing, etc. However,
he tried adding a filter that needed to be surface mounted to one of his
older Kenwood rigs, and he ended up messing up the PC board. The rig doesn't
work at all now, and he doesn't think it is worth sending it  anywhere to
have it professionally repaired. So, it is good to recognize ones
limitations! <Smile>

Ron, K8HSY