Skip to content
Back of the Box Builds

Back of the Box Builds

LEGO Alternate Builds!

  • SETS
    • Adventurers
    • Aquazone
    • Belville
    • BATMAN™
    • BIONICLE
    • Building Set with People
    • Castle
    • Duplo
    • Fabuland
    • Harry Potter
    • Holiday and Event
    • LEGOLAND
    • Model Team
    • Pirates
    • Space
    • Star Wars
    • Technic
    • Train
    • Town
    • Universal Building Set
    • Western
    • More Sets
    • Misc
  • USEFUL LINKS
    • Submit Instructions!
    • New Instructions
    • New Official Sets
    • New Alternate Builds
    • Minifigs
    • Very Small Builds
    • Small Builds
    • Medium Builds
    • Large Builds
    • Extra Large Builds
    • How BOTBB was Built
  • THIS IS AN INDEPENDENT SITE NOT AUTHORIZED OR SPONSORED BY THE LEGO GROUP
ABCs Alternate Builds Classic Space Classic Space Alternate Builds Instructions Added Space Very Small Alt Build Very Small Builds 

6901 – Back B

August 25, 2023June 23, 2025 Master Builder 3975 Views

From: 6901: Mobile Lab
Name: Classic Space Rover 2 1
Instructions: View PDF | Download .io File

*Alternate Build Connection: 1980 Medium US Assortment Guide (106917/107017-US), 6870 – Back A, 6901 – Back E, 6989 – Back A, 6984: Galactic Mediator

Contributions

  1. Name, PDF and .io file submitted August 26, 2023 by: Mr.AstonishedRaccoon
  • ← 6901 – Back A
  • 6347: Monorail Accessory Track →

You May Also Like

7119 – Back B

February 26, 2023February 26, 2023 Master Builder

6544 – Back C

July 20, 2022July 20, 2022 Master Builder

6505 – Back A

July 8, 2022July 8, 2022 Master Builder

6825 – Back C

September 16, 2019March 18, 2024 Master Builder

6030 – Back B

August 18, 2023August 21, 2023 Master Builder

2160 – Back A

April 25, 2023April 25, 2023 Master Builder

EXPLORE MORE OFFICIAL SETS

1680: Hay Cart with Smugglers
Castle Castle Sets Forestmen Official Sets Small Builds 

1680: Hay Cart with Smugglers

August 12, 2024September 24, 2024 Master Builder

Year Released: 1990BricklinkInstructions *This set is the same as 1877: Crusader’s Cart which was available in 1675: Legoland Triple Pack.

6088: Robber’s Retreat
Box Story Large Builds Ninja Ninja Alternate Builds Ninja Official Sets Official Sets 

6088: Robber’s Retreat

January 24, 2022April 3, 2024 Master Builder
6822: Space Digger
Classic Space Classic Space Sets Official Sets Small Builds Space 

6822: Space Digger

March 12, 2024March 12, 2024 Master Builder
1580: Lunar Scout
Classic Space Classic Space Sets Official Sets Small Builds Space 

1580: Lunar Scout

July 12, 2021July 12, 2021 Master Builder
6546: Slick Racer
Official Sets Town Town Sets Very Small Builds 

6546: Slick Racer

May 23, 2022May 23, 2022 Master Builder
4767: Harry and the Hungarian Horntail
Goblet of Fire Harry Potter Harry Potter Sets Large Builds Official Sets 

4767: Harry and the Hungarian Horntail

May 16, 2023May 16, 2023 Master Builder
5830: Fun-Day Sundaes
Belville Belville Sets Lion Knights Official Sets Recreation Very Small Builds 

5830: Fun-Day Sundaes

April 19, 2021April 19, 2021 Master Builder
6175: Crystal Explorer Sub
ABCs Aquanauts Aquazone Aquazone Sets Medium Builds Official Sets 

6175: Crystal Explorer Sub

January 20, 2022March 22, 2025 Master Builder
6495: Time Tunnelator
Official Sets Small Builds Time Cruisers Time Cruisers Sets 

6495: Time Tunnelator

July 14, 2021July 14, 2021 Master Builder
6856: Planetary Decoder
ABCs Exploriens Exploriens Sets Official Sets Small Builds Space 

6856: Planetary Decoder

April 16, 2021March 22, 2025 Master Builder
6818: Cyborg Scout
Official Sets Small Builds Space UFO UFO Sets 

6818: Cyborg Scout

July 18, 2022July 18, 2022 Master Builder
4559: Cargo Railway (High Speed Train Starter Set)
9V Extra Large Builds Official Sets Town Train Train Sets 

4559: Cargo Railway (High Speed Train Starter Set)

October 26, 2026October 26, 2026 Master Builder
6872: Xenon X-Craft
Classic Space Classic Space Sets Official Sets Small Builds 

6872: Xenon X-Craft

October 19, 2019April 21, 2026 Master Builder
6077-2: Forestmen’s River Fortress
Castle Castle Sets Forestmen Large Builds Official Sets 

6077-2: Forestmen’s River Fortress

April 19, 2021February 2, 2022 Master Builder
6356: Med-Star Rescue Plane
Classic Town Hospital Medium Builds Official Sets Town Town Sets 

6356: Med-Star Rescue Plane

March 16, 2022March 16, 2022 Master Builder
361-2: Garage
Classic Town Official Sets Small Builds Town Town Sets Traffic 

361-2: Garage

October 26, 2026October 26, 2026 Master Builder

BOXES

INSTRUCTIONS

FAVORITES

MINIFIGS

About This Site

Logo
There were once pictures of additional LEGO® builds on the back of set boxes. Written on the boxes was typically something about the endless building possibilities, "Build any of these exciting models with this set!" There were no instructions for these alternate builds, until now.

Sets

  • Adventurers
  • Aquazone
  • BATMAN
  • Bionicle
  • Belville
  • Building Set with People
  • Castle
  • Duplo
  • Fabuland
  • Harry Potter
  • Holiday and Event
  • LEGOLAND
  • Model Team
  • Pirates
  • Space
  • Star Wars
  • Technic
  • Train
  • Town
  • Universal Building Set
  • Western
  • More Sets
  • Misc

Useful Links

  • Submit Instructions!
  • New Instructions
  • New Official Sets
  • New Alternate Builds
  • Minifigs
  • Very Small Builds (<35 pcs)
  • Small Builds (<100 pcs)
  • Medium Builds (<200 pcs)
  • Large Builds (<400 pcs)
  • Extra Large Builds (>400 pcs)
  • How BOTBB was Built

In Honor of 1526

The classic space set that never was.

Copyright © 2026 Back of the Box Builds. All rights reserved. LEGO® is a trademark of the LEGO Group of companies which does not sponsor, authorize, or endorse this site.