After researching the 3.4L a bit, this looks like it might be the way to go for a '97.
The 3.4L PDF that is floating around looks really good, and it seems that the only major caveat to install is the ECU problem, but after talking to a couple of local shops, they told me they've done it, it was too much work, and call them back when I buy a Boxster S and want a 3.4 in it. (Which I'm kinda missing the point on I guess for the amount of $$)
Even so, this kit is still $7k + about $1500-2k in install (if you can't do it yourself, I'd say I probably can't
)
Sure is spendy to make these things reasonably quick. If the kit was $4k I'd be all over it a lot sooner.