MAKE the helix on the half tube of the p-block

CLICK ON PHOTO
TO ENLARGE

2. Loop the Main Group blocks



2. Connect both ends of Main Group

1. Fold up the long vertical joiner three-slot flap at the right side of the s-block and fold down the three tabs at the left of the p-block.

2. Lift assembly, loop the S- & P-blocks, line up the end tabs with flap slots, and insert all tabs in the slots from the outside - in any convenient order.

Here's where good lighting of the inside begins to be needed.
Lay model down with outside corners snug & even and tape (only) the bottom two tabs to the inside, and some of the flap near the bottom.