Looking at a new savage model 11.  From what I can gather online it should have the 4.4 inch bolt spacing and is the same action as a 10, 12, etc.  

Many stocks are listed as fitting only 10 or 10/12.  Why?  Will the basic new hs precision stocks that are listed for 10 or 10/12 also fit an 11?  If not what are the differences?  I can make the barrel channel fit if necessary, I'm just concerned about the actual fitting of the action into the stock.

I believe the difference would be in the barrel channels. 10/12 barrels are varmint/heavy contour and the 11's are sporter/pencil contour...so yeah, they will fit but you'll have some larger gaps in the barrel channel.

Only other thing I would pay attention too would be the bolt release type (not sure this is even an issue any more with the center feed stocks).

I thought all savage were the right side top lever bolt release now?  

What about converting to a box magazine?  This rifle has no floor plate, can I get a box magazine bottom metal and its that easy?  

Sorry to sound dumb, but I've never owned a savage myself so I'm not smart on them.

I said what I said about the bolt release because you may want to pay attention to what you get...i'm sure stock makers are still making them both ways.

As for converting mag types...I made the switch with my .223 12FV and the only change I had to make was to the bolt head BUT I think that was due to the chassis system I used.

Have you called Savage?

I bought a rifle last year and it has the bottom bolt release

The model 11 vs the 10 difference is the finish of the receiver/barrel.  The 4.4" screw spacing are for the newer rifles.  The older rifles had a 4.27" screw spacing.  OP referring to it as the "bolt spacing' threw me off.

Savages latest rifles have the bolt release on the bottom.  I like how Savages shoot and the DIY nature of the rifles, but I cannot stand Savage because every few years they keep on changing shit on the rifles.  This is one reason why there isn't a huge after market support because they keep on changing specs. Savage warranty sucks at only one year from date of purchase.