There is oil on the 959's front valve cover and everywhere else, lower cowling etc. I just need to reseal the rocker cover, simple enough job in theory but in practice working on these things is a nightmare.

Take your time. Get a service manual and get a new gasket. Wipe the gasket surface on both parts clean so no oil has a path started. Use a good sealant I used the sealants that were recommended in the service manuals but they're insanely expensive and sometimes tough to find plus they'll probably be hard if you ever want to use them again. This will probably be very similar to replacing a ZX-14 valve cover gasket, there's a special sequence the bolts are supposed to be tightened in to get the valve cover settled in place flush.

The 14 has burned oil since new but otherwise solid.

I noticed by the second oil change, my 08 ZX-14 was using oil somewhere. The valve cover leak contributed a lot but I know in my heart, it still used a little oil between 2500 mile oil changes after I fixed the leaking valve cover. No big deal, it ran good. My Gen2 had oil changed at 600 so not a fair comparison but the oil level looked the same as when I first started it. The Hayabusa never used a drop of oil either. I don't know what it is with these 14s but like I said, if it runs good, that's all that matters. I believe I had to add oil before the valve cover leak was fixed but that was pretty simple.

---