- Don't worry about the surface rust upon the (outside) end of the sprocket splines*
Ignore the chip marks on the gear dogs in your pic #4**
Do check the 'squared' (flat) end of the lifter rod for a scribe mark from the 8x21x6 oil lip seal***
Read, re-read and then read again and digest Bill's Techknuckle pages from p92-100!
- *Do clean the outer diameter of the shaft and apply a turn of thin, brown packing-case tape to the spline when fitting the seal so as not to damage the inner lip of the seal
**Do get the transmission shimming right (then you'll only need to do it once!); note that the dogs aren't square castellations, but have a slight inward taper to maintain engagement; consider 'X'-ing the gears. 'Shimming the tranny' -- a particularly popular past-time in Bangkok! -- is essential (p100)
***If there's a groove, deep enough to feel with a fingernail, circumventing the lifter rod about 15mm from the flat end, try to obtain a NOS rod on eBay -- it will almost certainly leak in use. If you can't get a better or NOS rod, consider having the Clutch Lifter Piece (13, p70) flange machined by about 1mm so that the lifter rod will end up intruding through the seal slightly more, thus allowing the seal to sit in a different place.