I have a problem with my shifting pattern. I own a 1995 Isuzu Plaisir Bighorn. My RPM always fluctuates when I'm going over 60. I had it fixed already but the problem is back. What can I do or what should I tell the mechanic when I get it fixed?

Btw, where can I get an original left-hand drive dashboard? Mine was converted from Subic and the dashboard they put in replacement is pangit. (parang minasilya lang).

Thanks.