Josh,
I am building something very similar, but I have increased the internal dimensions to try for an F3 point more similar to a pair of nOrh 3.0's. I do have a complete set of plans for the ELF 1.0 and it calls for a 1" diameter port that is 3/4" in length. CSS sells them pretty cheap, but you have to cut them as they come 4" in length.
I am curious as to the veneer you will be using. Is it the iron-on type or something else? Also, did you round over the edges of tha baffle to make veneering easier?
Regards,
RDS