Thanks - so, I did the swap a couple of weeks ago and have been troubleshooting ever since - thanks Vandrid for your help on another post.
I've started a thread in the Restoration section for future updates/pleas for help:
http://www.fiatspider.com/f15/viewtopic ... 30&t=36378
In case others are reading this with the same swap in mind I'll leave my somewhat random thoughts on the project here as well...
- I suggest putting the whole car on jack stands for the work - some of the manifold bolts were more accessible from underneath and you're going to spend a lot of time leaning over the car. This would have killed my back otherwise.
- Even with draining the suggested amount (1 gallon) of coolant, when you loosen the intake manifold there will still be coolant leaking out, especially from the coolant line at the right end of the manifold for the water choke. Wish I'd had a bunch of shop towels stuffed under the manifold.
-I've read many posts about how hard it is to get the intake out even after you get all the nuts/bolts off. This was a total pain, until I decided the studs had to come out too. My car had two studs and the others were bolts. Since the original intake is so wide it is blocked from pulling out by the timing belt rear cover (if you still have one). Removing the mounting studs allows you to slide the intake to the right. Used the 'two nut' method to back them out. Be prepared for more coolant leakage from the stud holes.
- as for the carb, I ordered the k-518 kit put together by Redline. Shop around online -prices vary. Parts needed to connect throttle to rod are included, along with many unneeded bits for other installations. Importantly, I ended up having to take the top off the carb for troubleshooting and found metal shavings and brass 'sand' in the float bowl of whatever cheap metal the carb is cast from. Not impressive QC from Weber. Also the nut holding the linkage to the throttle shaft kept coming loose, and the little tab that bends over the nut is a joke so I'm trying some thread locker to see if it will hold.
-Finally, During my first post-installation test drive, the secondary idle jet and holder fell out somewhere on the highway. I have invested a lot of time learning about my carb trying to troubleshoot this problem...wish I had invested that time and dismantled the carb and learned something before rushing into installation. Not sure I'll ever learn this lesson though.
-Most importantly, it was worth it! Still working on the tune, but I'm amazed at what a difference this made in the car. Need better brakes now.