I know the pro-comp subject has been utterly beaten BUT...
I recently purchased a set from tri-state heads.

[2.05x1.60 valve size 60cc/210cc runners]

Tri-state did a fine job with the troubled areas and made recommendation on the correct valve train to keep the proper geometry.

My question is on the valve guides and how to handle that area when blending the guide to the chambers. These guides go at least 1/4" beyond the chamber. Can I shorten them to blend them in?
How long should the guide be to keep the valve stable?