Can I use an outside feeder tap to run power to a garage?
I would install a 60a fusible disconnect to the right of that enclosure using a PVC nipple. Then polaris tap or insulation piercing tap both ungrounded and grounded conductors. Probably 1/0 between the tap and the line side of the disconnect would be sufficient. Also reemember to install a ground lug in the disconnect, keep the ground and neutral isolated in the disconnect and run the ground al the way back to the can on your picture.