I just bought an 11-87 last week.  It already has an 18" barrel w/ 2 shot extension.  I plan to change the rifle sights to ghost ring, and add a side saddle, light, extended bolt handle, stock w/ pistol grip, and big head safety.  Which stock would you guys recommend?  I'm leaning towards the speedfeed with the shortened LOP.  Also, heard of some people modifying the bolt release for easier access.  Is that just a replacement bolt release, or does the one currently on the gun have to be modified?    

Let me help ya. Speed feeds are nice get the shorter one. The charge handles are changed in seconds. No modifications. Brownells sells alot of stuf for the 11-87

I think the "bolt release" you're asking about is the DMW "Easyloader".
This is a stainless steel extended lever that replaces the standard carrier release button on the carrier.

This longer release has a groove that aligns the shell, and to load, all you have to do is push the shell into the magazine like you do on a pump gun.
When you push the shell in, the carrier is automatically unlocked by the longer release.

You can buy this from Brownell's Gunsmith Supply:
DMW Easyloader for Remington 1100/11-87.  #260-100-000   $29.95.

www.brownells.com

Most people who run HD or Combat Remington autos use this.