Man you are working quick!!!!!!!
The bottom end looks better than the top.
Your not wrong. The gearbox looks very good.
The barrel is at 57.5mm and I recon if I bore it to 58mm its last bore size
only 0.22-.25 mm will come off each side so I don't think it will get all the corrosion out of it with the pitting quite bad in few spots (in the top 30 mm of the barrel of course)
I'm looking at other options. No point spending $100 on a rebore to be told sorry its beyond repair.
I'm considering sleeving as I can get a LA sleeve for about $100 delivered I think. I have access to a 20 ton press at work and a mech engineer in charge who wants to fit out his workshop to fix bikes cause he loves em too:)
I think I'll watch a few vids
I'm looking at options at this moment in time.
Other options include buying a s/h one off ebay from the states etc..