looking good fgt
How is the welding going ?
If you haven't got the outside patch panels in, send them back! Just boatside it instead. Would be way more functional
Are you using .030 wire on the sheetmetal?
Try .023, it needs a lot less power to melt and you can actually carry a bead on thicker sheetmetal, at the very least you can tack effectively. Another option that's really helpful, but spendy nowadays, is a copper backing bar. The copper both whicks the heat and allows a backing that won't fuse to the steel.