5.3 build help needed

I am not very familiar with the LS engines. I have always wanted a Shelby Cobra but the US Army dosen't pay that well. So I am planning a V8 swap into my 2002 Miata. I have seen your 5.3 build in the April issue and am impressed. Maybe you can help me with the parts list. Here is the direction I would like to go. I looking to start with a low milage salvage aluminum block 5.3 with the displacement on demand. I hope not to rebuild and it would be mostly stock but I'm planning to install a aftrmarket cam but don't know if one is offered for the DOD engine. Power goals will be 375 or higher if possible. I know it is a transverse mounted engine but don't know if it would accept camaro accessory drive to correct that. The DOD requires the electronic throttle body but I need to change to a intake with the opening in the front. Could I turn the intake around or use the LS2 intake with a the possibly too large throttle body. Also, would LS Edit work with the Impala/Carlo computer with the DOD. In your article you used the truck engine; are the car and truck heads the same? For the transmission I need help with which bell housing, flywheel, and clutch assenbly to use. The easy way would be to use the Camaro T-56 but it is a little large and heavy for my needs but the shifter location is correct for the Miata. I would like to find a lighter weight aftermarket 5 speed with proper road race gear spacing and a lightweight flywheel for faster reving. A heavy flywheel is not needed in a 2400lb car. Now for the bonus question. I would like the car to have a Ferrari sound any advice on mufflers or exhaust tips.  

Aluminum block 5.3L motors are fairly rare, you're gonna have better luck with an iron block motor. Or if you want and all aluminum motor, find an LS1 to buy.

This swap has been done before, poke around the Miata forums and ask the guys there for advice.  

I am familiar with the swap and have a large collection of pictures and information on the installation. What I dont have is a cheap alternative to a $6,000 LS1 and T-56 from a Camaro. I did find out that the Impala/Carlo have a shorter crankshaft where the harmonic balancer mounts so it looks like the truck is the only other alternative. But I also found in my research that the LH6 and LH8 are aluminum and have DOD and run E85. Now for the lighter transmission.....