I've been researching this for about 6 months and will be upgrading to the Rack Attack or Flaming River next month - I'm leaning toward the Flaming River.  It seems to me, based on all the different posts I've read on many forums,  that the Borgenson is more for aesthetics since it looks similar to the original steering box and performs a little better than a complete rebuild with trouble-free maintenance.  So its a matter of preference for purest or performance - I choose the "bolt-on" performance route myself.

As for clearance, I've spoken to a few Vette repair shops in the Atlanta area, and they all say the same thing, that all the rack and pinion kits require some modification to the install instructions - so I personally would have a reputable shop do the work.  And as for turning radius, the Flaming River maintains the stock radius with no bump steer issues.

I haven't looked at the Flaming River kit... I'll check it out...  as for shortening the steering shaft for the Borgeson install... what is involved in that? Do you just cut some off the end of the shaft?

Thanks

Lonnie