pair of these
http://www.superbrightleds.com/more...ed-45-degree-viewing-angle-4500-mcd/311/1243/
it'd be tough to do for sure... they'd probably need to be installed from the inside with a bit of epoxy into drilled holes.. and you would probably need a boroscope, and some funky needle nose... plus they would probably need to be pre-wired as an assembly.... at least routing the wire would be easy, being hollow...
maybe if I get bored one winter... 
http://www.superbrightleds.com/more...ed-45-degree-viewing-angle-4500-mcd/311/1243/
it'd be tough to do for sure... they'd probably need to be installed from the inside with a bit of epoxy into drilled holes.. and you would probably need a boroscope, and some funky needle nose... plus they would probably need to be pre-wired as an assembly.... at least routing the wire would be easy, being hollow...
maybe if I get bored one winter... 

Green is of a wavelength that can be easier seen by the human eye, therefore brighter.
I'll take a peak at it this weekend and see what i think.... the mount shouldn't be bad.. just gonna holesaw a slug of composite out and shape as needed...