Well... Part of the problem with going to a six-speed is that it's tough to find used ones, and the new ones are expensive (around $7K, I believe, and that doesn't include labor).
At the same time, the '97's are now four years old and have declined some in value. It's not unusual to find them for mid to upper fifties. And, in addition to the six-speed, they have a host of other improvements, including the bigger engine.
On a cost-effectiveness basis, thanks to both these factors, it's getting easier to justify trading in on a '97, and tougher to justify retrofitting the six-speed to an earlier car. Doesn't mean you can't do it, but there's more of an economic case for just trading in on a newer car. Or, as you note, going to the short gears and R&P is another option.