Hey All! I'm a small maker (one man operation, but I have thousands of 5 star reviews) and created some mounts to store your crossbars in the bed when not in use. I initially made them for myself, I only have one set of bars and didn't want the EV sportline's more expensive and bulky 4 bar mount. Figured others would want this solution too.
They are 3D Printed, but out of automotive grade carbon fiber reinforced ASA, they're ultra sturdy and UV/heat resistant (I've tested them thoroughly and they're super tough).
The weight of the bars is mostly supported by the bed, the mounts just keep them in place. Crossbars just pop on and it keeps them from sliding around the bed and frees up space in the gear tunnel when the bars aren't mounted up top. Includes mounting hardware and take less than 5 minutes to install.
Can get them here: https://www.tycotech3dprinting.com/products/rivian-r1t-crossbars-bed-mounts There's a video on the listing showing how they work and install. I've created a discount code just for this sub, use code RivianReddit10Off at checkout for 10% off (code is valid till the end of the week)
Please let me know if you have any questions!!! Cheers!