Response from LEGO SHOP
29 May 2020
Samuel, LEGO Customer ServiceWonderful, we have some great news for you! You can combine the LEGO® Technic 42090 and 42091 with the use of our building instructions Ultimate 4x4. You can find this by searching for set 42090 on our instructions service page at LEGO.build/BI-BV Enjoy the challenge!