-Place the fore-end assembly over the mag tube.
-Position the slideblock assembly and breech bolt assembly onto rear of action bars.
-Guide the action bars into the receiver until stopped by the right shell latch.
- Push the carrier upward, depress and hold the right shell latch.
-Slide the fore-end rearward until stopped by left shell latch.
- Reach into bottom of receiver . Depress and hold the rear shell latch.
-Slide fore-end rearward until stopped by the action bar lock.
-Push upward on the action bar lock. Slide the fore-end rearward approx. halfway.
-Replace the bbl, and mag cap.
Directly from the Users manual, a very OLD one, but applicable. Holler at Remington they will send you one. Sorry I don't have link to their site, but I bet instructions are avail that way also.
HTH
Edit to add link.
http://www.remington.com/default