Estes Star Seeker BT-50 Upscale (Tri-Pack) Kit #0866, Part 8, Nose Cone and Shock Cord Mount

On the Apogee plastic nose cones, 

there is sometimes a raised lip on the shoulder edge.

Sand this down a bit.

The nose cones can have a slight bulge at the tip.

You can sand the tip so it follows the contour of the nose cone sides.

The shoulder cap was glued in using Beacon Fabri-Tac glue.

If you can't find a good plastic glue (most don't contain Acetone to "weld" the plastic pieces) Fabri-Tac is a good substitute.

Run a ring inside the nose cone, slide in the base and turn to even the glue bead and get better coverage.

I don't normally use a tri-fold mount, 

I didn't feel good about a Kevlar loop under the upper (homemade) centering ring. They're probably strong enough to handle an ejection pull, but I played it safe with a folded mount and elastic.

A 12" Odd'l chute was tied onto the shock cord.