I recently picked up a VXL Slash off of Ebay, and after a few weeks of bliss, unintentionally "welcomed it home" by smashing it into a pole off center at full speed, breaking the front bulkhead and tweaking a bunch of other bits. The suspension already had RPM arms, aluminum turnbuckles, steering blocks, bellcranks and other goodies so it held up well.
At any rate, I ordered the FLM bulk, some new pins and started piecing everyting back together. I found out the previous owner had the steering linkage set up all wrong. There are several steps that need to be taken to get everything set up properly so the steering responds the same when turning in each direction.
1) With bellcranks set to center (pointing straight ahead), the steering turnbuckles need to be adjusted so the wheels are pointing straight ahead.
2) With the bellcranks set to center (pointing straight ahead), the servo needs to be set parallell to the drag link coming off the bellcranks. This is done by setting the servo steering link to the correct length.
3) When all this is done (everything is set up symmetrical and parallel) then the system can be adjusted for toe in/out etc. Otherwise it just won't work right.
I will post pics later, until then this should match some existing suggestions.