Chris,
 
Christopher Lemmer Webber wrote: 
> Anyone more familiar with the linux build process who can give 
> me some tips?  Especially since I board a plane very early 
> tomorrow morning :) 

My own kernel package has nothing left in common with linux-libre, 
but it does build from git and has this phase + comment which I'd 
hoped
would never see the light of day:

  (add-before 'configure 'fix-CPATH 
    (lambda _ 
      ;; Temporary hack to remove -checkout/include which breaks 
      things.  ;; Why is this not necessary when building in a 
      ‘guix environment’ ;; and in the Guix linux-libre package? 
      Git-checkout-related?  (setenv "CPATH" (string-join 
                       (cdr (string-split (getenv "CPATH") #\:)) 
                       ":")) 
      #t))

I'd remove it to see what happens, but that would be tomorrow and 
you appear to be in something of a hurry. 

Good luck!

T G-R