Yes, the 4.6 swaps allow for a flat bulkhead.
Here's a like to a 4.6 DOHC swap, with some better info:
http://home.earthlink.net/~rlbpantera/
The 5.0 Coyote is definitely more advanced and more powerful, yet lighter and more compact than the 4.6 DOHC Modular.
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