[Newbies] Using same class names

[lanas]

Hello all,

 Is there a way to have several classes with the same names and having
their scope limited to the current selected category ?  Eg.  I'd like to
experiment with the Abstract factory pattern and thus I would like to
make several tests, each in a category, like:

AL-AbstractFactory-1
AL-AbstractFactory-2

... and so on.  Each one is a variation and experiment. So I'd like to
keep the same class names but Squeak warns me that the CarPartFactory
I'm trying to create in AL-AbstractFactory-2 already exists in
AL-AbstractFactory-1.  Do I have to file the category out, remove it,
create a new test, file out that second test, remove it, then file in
the first test and such ?  

In other words, is there a way to quickly switch from one experiment
to the other when each of these experiments would use the same class
names and probably many of the same method names ?

By the way, in the System Browser, the row of buttons labeled browse,
senders, implementors, version, inheritance and such has
somehow disappeared.  Any new System Browser does not have that row of
buttons anymore.  Is there a way to bring them back short of reverting
to the original image.  This is Squeak 3.10.2.

Thanks for any suggestions,

Al