Another option would be to cut the cross member along the angle for about 1/2 inch and bend the short side in to create your mount bracket, use 2 screws to prevent pivot. Interesting build, Would love to get my hands on the plans for that gear box, that took some time to draw up!
Thanks! I am going to install the gearbox in a later video, but I used the bolts to connect to some brackets which were mounted onto the frame. This is the link for the tyres: www.ebay.com.au/itm/4PC-96mm-Tyre-RC-1-10-Off-Road-Climbing-Car-Beach-Rock-Crawler-Tires-Wheels-Rim/233700822719?hash=item3669a78ebf:g:kngAAOSwWkFcj0Nl
