I have been very slowly working on this swap into a 71 cuda over the last few years. I am using a 5 speed standard tranny in the swap so I cannot comment on the automatic transmission. You can get motor mounts and an oil pan that will allow you to drop the 5.7 right into the b or e body, that is the easy part. If you are electronically inclined the stock harness from the 5.7 can be modified. I suggest you get the 5.7 from a charger rather than a truck it has a neater accessories layout and a nicer intake setup. I am also using the 6.1 factory exhaust manifolds that I bought on eBay. I bought my 5.7 from a junk yard a few years ago before the 6.1s were out, it came from a Charger and had about 30K miles on it, I paid $500 for it, used www.car-part.com to locate it. The big money is going to come with the ignition and computer to run the motor, AEM and FAST have turn key solutions for the 3rd gen hemi. I hear MegaSquirt has the 3rd gen hemi tone wheel figured out now so maybe you can go that root, figure $500 bucks for megasquirt DIY solution and $2200+ for FAST or AEM. The other big expense is the fuel pump and tank for the FI, depends on how much fabing you want to do or adapting fuel pumps from junk yard donors otherwise turn key is going to be $600+. There are a lot of nickle and dime things that will add up but if you keep your eye out on eBay and other places and scrounge the junk yards you can do a 5.7 swap for a reasonable price. When you put the 5.7 up next to the 440 and I have both in my garage next to each other, the difference in technology will be obvious, precision light weight casting, O ringed seals, tubular exhaust manifolds, FI setup etc. I encourage you to go the restomod route and plant a 3rd gen hemi in your ride.