The S14 is much easier. For the front, you need S14 SE hubs. Just unbolt your 4 lug hubs and bolt on the 5 luggers. You can find these in the classifieds from someone parting out an SE or in local junkyard (kinda tough to find). You can buy them new from a sponsor (EverythingNissan.com) for $100 each. I think new front hubs only come with bearings, so if yours are shot, this is prolly the best route.
For the rear, you can use S14 SE, Z32 nonturbo, or J30 hubs. I'm not 100% sure on the J30 as Ive never compared them, but word is they can be used. These bolt on as well.
Heres a link with the basics.
http://importnut.net/300zxbrakeswap.htm#5-lug
Seach for '5 lug swap' on NICO for more detailed info...
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