So, I went out and bought a sled load of 320 wet/dry paper and after some sore fingers brought things to this:
Yup, that's my bed the frame's resting upon. My wife is very forgiving

The blemish in front of the rear indicator mount is where I had just JB welded a 2mm hole but not sanded back the JB yet.
Sanded:
Sanding back a spot weld:
Head bearings were worse for wear, to say the least:
I then looked under her skirt:
That's going to require copious application of elbow grease.