I have never met a carbine I didn't like {almost}, and I never get too far away from a hacksaw when I get hold of a new rifle...

I doubt you will take me up on this, but my suggestion is to take your unfinished-barreled rifle, rig a front sight and start chopping. Start with a 25 inch tube and play around with it. If you think it is too gangly, lop an inch and do same. If 24 is still too short, cut again, and so-on.

Taking a hike with the rifle and firing a few shots at each length along the way will give you an idea of handling, performance and muzzle blast, and if your increments aren't too much you'll know when to stop before you chop too much.

Sounds like a lot of work, but seriously, on a specialty gun like you are talking about, why not? It is a one-time deal, built for you by you. Who cares what others think so long as you do not see the gun as a resale object. Of course, having said that, one-offs sometimes bring more than they "should".

I say go for it, cavernous case and all. If you like it, have at it. If you decide to go this route, PLEASE write it up, photo the process and post here. I think it would be a fascinating experience and your experience would make for very interesting reading.