Here's the Rocksim File - note that the instructions on rocketshoppe.com are TO scale. If you do NOT check "fit" when you print on 8.5 x 11 paper, fin templates and more importantly, the roll alignment guide are correct. Check your printer though, take nothing for granted!
Note that on my fin alignment roll guide, it "looked" like it was too small - very small amount of diagonal lines from the underlying flap visible but worked perfect.
https://plans.rocketshoppe.com/estes/est2030/est2030.htm
I just knocked a 1:1 scale rocket together using 3/32" papered balsa - a little thick but sturdy. I think this rocket needs sturdy. Glue rivets under the fins and thoroughly primed with TB2 and filleted. NC from E-Rockets or Estes - I had a very old one in an old Designers Special I got at an estate sale. A little draggy but fine for a sport rocket - Rocksim is sensitive to "10" instances of interference drag from the fin-body tube joints.
Not worrying about the decals - have some checkerboards laying around and want to do a "fade" Air Superiority camo with my Paasche airbrush. Maybe some colored stripes designating propellant, explosive, etc. Bright chute required : )
Going to do a 2 stage BT60 upscale for 18mm motors for economy and getting the upper stage back. Main fin placement is an issue and will have to overhang the end of the upper stage a bit to be scale.