I did a tear down to replace the shift linkage about a year ago, you have to split the cases. Not that hard if you have the time. Get a Clymers manual and look up video's by Roach on an engine teardown, it will give you a good idea what's involved. Cost was probably around $200-$250 with all the new gaskets and such. From what I've read you probably close to the $800 for a mechanic to repair.
Also on a side note, pull the rear wheel and lube the shaft splines when you have it apart. That could lead to a big problem later if it hasn't been done lately.
"Show me a man who makes no mistakes, and I'll show you a man who doesn't do things." Theodore Roosevelt."
2007 Victory Kingpin
Current projects - 1986 VN750 & 1988 EL250