Can these be linked to give me 8 channels? I saw this cable on the Sound Devices website.
http://www.sounddevices.com/download/guides/xlta35_en.pdf
Will it work with the mix bus on the FP33?

I don't think the FP33 has the same "mix out" that the 302 does. (I may be wrong though)

A cable that would work is the XL-TA25, which connects to the "Tape Out" jack of a MixPre (or in this case the FP33) and converts to the 5 pin 552 connector.

You might give this a try.
Remote Audio Shure FP33 and Sound Devices 442 Link Cable - Mixer Cables - Cables, Connectors & Adapters - Trew Audio (http://www.trewaudio.com/store/product.php?productid=191&cat=0&page=1)

All the Best!

if you don't need 8 ISO tracks, then just take a mix from the shure into one channel on the 552. If you do need iso tracks (which recorder are you using....?) then why not go with some feeds directly into the recorder and forget the shure?

Thanks for all the responses. I called Sound Devices and they said that the mix out on the FP33 is different than the 302 so I should go with the XL-TA25 as Alex suggested.

The remote audio cable will not work with the 552 but the guy at SD guessed that they will have something soon.

Karl, your solution is the least expensive.(free!) I don't need isolated tracks, but I do need all 8 inputs. I am taking all eight mics to a mono mix.

I'll probably go with XL-TA25, thanks again.