No wonder I had so many issues with the C4 in my '67 F-100 (it came along with the 351C out of a '73 Torino GT). Had I known that then...

Anyhow back to the carb for carb, FI for FI: Not all states, but some states will make you pay extra for the changeover in fuel delivery, because of the differences in emissions and all that junk. Plus, a lot of times, it just makes things easier, unless you not only feel like tearing into a wiring harness, but at the same time ripping a bunch of it out. That's just my opinion, though. I can't remember the site, but there was one I remember seeing about the whole issues as far as "keeping it stock/OEM looking" and the in's and out's of the legalities by state, etc.

I've been working on plans for down the road and tinkering with some ideas for power/economy gains for my what-will-be-mostly-stock-but-modified 2.9, such as a water-vapor injection and mixture controller setup, among other things. Still mostly brainstorming, because I'm not planning on ever doing another V-8 swap... if anything, I'll up to the 4.0L V-6 out of a Ranger or Explorer -- I just need to do some research and recon on it... because if the engine uses a normally-distributor-mount hole for the CPS.... I have some ideas on how I'd prefer to go with the swap as to not have to do a bunch of meddling with wiring harnesses. Good luck again on your swaps!