Whats the big no no about welding rods they work way better than super glue. If this was a modern over the road rig that had to meet dot specs bring out the bolts. It's not and I have been using these old boom trucks all my life built like this with no ill effect. I've had more trouble with bolted together stuff failing than welded. My old truck gets used long and hard handling loads it was never ment to see and nothing has failed yet.
