Keep a dir at the top of load-path??

[ned]

I have built a handy .emacs that lets me run either Emacs or XEmacs
depending on my mood.  

The only problem is that I want to byte-compile my various .els with
one or the other.  I want to specify an Emacs byte-compile destination and an
XEmacs destination and have them be called first from the load-path.  

So the question is how to keep an entry as the first entry in
load-path no matter what gets added subsequently.

Does that make sense?
-- 
Ned Ludd