You might want to use a dab of white lithium grease on the sliding part. I think any grease would work. An access panel is not a bad idea. Sometimes you need to dig in and fix something that is sticking or binding. Make real sure the bellcrank works VERY freely before you install it. I sometimes spend hours watching TV and working a new bellcrank in. It must work smooth and free in order to work correctly.   Mike  ~

Thanks for info I spent about an hour sanding ,grinding and clearanceing. Thanks John