To use a modern term it is "plug and play"... It comes out of the dash clean and is in a sealed "can".. No adjustments can be made..(without jacking the can open..) Yep I have done that too. The only adjustment is the number of teeth on the gear.. It might be the needle is running on 20 year old grease but usually it is the cable or gear that causes the jumping.
Big Jim <img src="/forums/images/graemlins/pfft.gif" alt="" />

professional bovine relocation specialist