I've played SSB a few times under Project64k. I think it works rather reasonably; you shouldn't be getting these graphics issues. Specify your graphics card, please.
But if you want better graphics you should take the latest Jabo's plugin from PJ64 1.6, rename it to what it's called in PJ64k and use it instead.
If you mean renaming the dll file, that won't work. If you mean renaming the internal plugin name, that might just work in a sense, but you'd need a binary editor to do that. I use MS-DOS, but even then, Jesus, it seems that Jabo's plugins are encoded in a way that prevents this, so I cannot test this out.
Inevitably, Jabo's Direct3D 7
will, therefore, be loaded on KailleraClient initialization unless you use 1964 or Nemu64 instead. May I suggest using glN64 on 1964 emulator instead? If too slow or missing graphics, switch back to the infamous Rice's Daedalus for pretty good speed and fair enough graphics. Graphics can be improved later.