Tom,
Mike pretty much covered the TWMs. I have the 50 mm on my engine, 351W bored stroked and internally balanced. I think it comes out to 392. Will have to look up my shop order. That was soooo long ago.
I am using the FAST XFI and it is a good setup. Great support and they hold classes for those that want to learn the system.
Fuel Air Spark Technology - Leader In Electronic Fuel Injection There is no setup that they can't handle. I am using LS-1 coils and 36 lb. injectors. They have a small forum that you can ask any kind of question and there is someone who can give you the answer, or you can call them and they will help you with any problem you encounter.
I decided that I wanted to go with a distributorless ignition so I have the XIM box as well. Sensors are standard. I am using the MAP, water temp, air temp TPS, and O2 exshaust sensors. Since I have the XIM there is a crank trigger and cam sensor as well.They can supply you with all the parts you need if you want them to do a seamless setup.
From FAST:

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NEW BOLT-ON KITS INCLUDE EVERYTHING NEEDED TO CONVERT POPULAR FORD ENGINES TO EFI
FAST™, the leader in fuel injection technology, introduces the industry’s only “truly complete” electronic fuel injection (EFI) kits. Other manufacturers sell partial kits that require you to source hard to- find parts; this only increases the expense, guesswork and headache of installing EFI. To solve this problem, FAST™ has included every single component needed to install fully sequential EFI on Small & Big Block Chevy and
Small Block Ford engines from mild street rods to 1,000 hp all-out race cars.
To solve this problem, FAST has included every single component needed to install fully sequential EFI on
Small Block Ford Engines, from mild street rods to 1000hp all out race cars. Another key component included is the revolutionary FAST™ Dual-Sync Distributor. These innovative new distributors allow fully sequential operation, yielding better performance, improved idle quality and more precise tuning as compared to old technology bank-to-bank systems.
The kits also include a single plane aluminum intake manifold, Big Mouth 4-Barrel Throttle Body™, proper size Precision-Flow™ Fuel Injectors, aluminum fuel rails, fuel pump kit, all necessary sensors and professional quality wiring harnesses with labeled connectors. Most importantly, to ease the anxiety and fears often associated with an EFI installation, FAST™ has included its highly-regarded EFI Installation & Tuning DVD containing two hours of step-by-step installtion and tuning advice. Throw in the fact that this product, like every FAST™ product, is backed by the industry’s finest tech support and it’s easy to see how FAST™ is the one company that has removed the fear and intimidation from EFI.
The DVD makes everything easily done. You can download their C-COM software and it is step by step. They incorporate real time data logging so you can fine tune the engine to whatever you want. You can have a few parameters or as many as you want. The standard setup has about 14 things to look at, from rpm to battery voltage, Ve, Ign.(BTDC) and A/F.
Their first startup routine is simple enough for even me to follow!!
Bill