Thought about that...I could get to pretty much stock width within the 9" factory specs, but I'm going to need adapters in the front to run 5x5.5 front and rear (need to buy new wheels $$$) so then that would make the front wider than the rear (unless I ran spacers on both axles $$$)
OR I could cut it to 63, order up custom 35 spline shafts drilled to 5x4.5 ($345 from Moser) keep my stock wheels (saves $$$ on new wheels and mount and balance) and just run some 1.25" spacers in the front to keep the width even...
What are you going to do in front then when you jump to 37's? Gonna be putting a lot of faith in that HP30. Going 5x5.5 might cost you more now, but it leaves more options open for when you upgrade in front.
To be honest I doubt it is even a real issue. If you are getting custom shafts it is just a few bucks more to get them drilled for 5x4.5 AND 5x5.5. Lots of aftermarket chromo axles come with both patterns already drilled that way off the shelf.
Just out of curiosity, if you are looking at all the work and money involved in narrowing and building a rear axle, why are you so dead set against narrowing a D60? You spend roughly the same money, and end up with a stronger axle and better driveline angles. Or even cheaper yet, a 14 bolt. There is bunches of info on shaving and plating them, and they are even cheaper than ford 9's.
Personally, if I were going to attempt to narrow an axle and build a custom rear by myself for a TJ, I would not bother with a 9". It is just too problematic to do well unless you want to go HP, which you don't. And I have much love for ford 9's, since I am running a Currie HP9 in front.
I really thought about it last year, and nearly pulled the trigger on a big bearing 9", but after I started writing down what I would need to do to get it to fit, I wasn't saving any money at all. By the time you are done making all the compromises you didn't want to make just to get your $75 axle to fit, I would be willing to bet you are pretty near the cost of a rear RockJock D60, which is a far superior axle with no compromises.
Best of luck whatever direction you go though!