There are only two differences really with the stroker. The crank, and the pistons. The rods are the same. The crank has a 4" stroke instead of 3.31" for the 318/340's, or 3.58" for the 360. The pistons then have a different pin height to adjust, and a shorter skirt length. You do increase the sideloading, but even with the 4" stroke the rod ratio isn't that bad, there are worse combinations out there. With a good block, it won't be an issue. The 4" stroke cranks have been around for awhile now, lots of people run them without issue. For price, you lose money on the crank, but most aftermarket rods don't cost that much more than refurbishing/resizing a stock set of rods with ARP bolts. Piston cost is about the same, and you're already planning aluminum heads that flow better.
I don't have a 340 stigma. I run one, I love it. But having said that, there's no reason to prefer a 340 over a 318 or a 360 for a non-numbers matching build. All they do is cost more. The historical significance associated with them had everything to do with them being a high-performance factory engine, if the 318 or 360 had ever come in a high compression, 4 barrel engine with a slightly bigger cam (like the 340's did) they would be just as revered. If I was starting with nothing, I'd buy a 360 block over a 340 every single time now. The 340 gets all the love because of what it was from the factory. A 360 rebuilt to the same specs will do just as well or better, and if you have to buy the block you can save hundreds going with the 360.
Honestly, I think the 408's are the way to go unless you go big block. The thing is that while you can build screamer engines that make a lot of power, you lose streetability. That's what I'm looking at with my 340. Its a strong engine, but mostly over 3k rpm. It's a beast between 3k- 6k. But on the street, that's not where you want your rpm's to be. I could make more horsepower with a 408 and the resulting build would still be easier to drive on the street.
A 26" radiator fits just fine. You don't even need to open up the radiator support for the larger radiator if you don't want to. All you need to do is add the new mounting holes. And if you do want to trim the radiator support it's just cutting about an inch off of either side of the radiator opening.
If you go with a 130-140 amp alternator you'll absolutely have to bypass the alternator gauge and bulkhead connector. If you put that much power through the bulkhead connector you'll burn your wire harness to the ground, if not your car. But since that's a 1 wire alternator with an internal regulator maybe that's your plan. I've been running my Duster with the stock amp gauge and bulkhead connector using the 100 amp alternator. I did the same on my Challenger for 60k miles, but the Challenger doesn't have the same kind of draw because the fan on that one is still mechanical.
You won't find any Mopar Performance bars bigger than .94" for the A-bodies, they haven't been making the larger sizes. You'll have to go aftermarket to go bigger than that. PST gives a FABO member's discount if you call them, and their 1.03's are a good rate if you're not planning autoX or anything like that. The only way you'll be happy with larger bars is without the KYB's. Those things are terrible. I ran my Challenger with 1.12" bars and KYB's for like 50k miles, changing to the Bilsteins was such a huge difference it was like a whole new car. KYB's are for garbage cans, not cars.
No, US Cartool makes one that fits right up agains the stock lower support. I have a tubular brace on my car, but the source is no longer in business. Here's the US Cartool piece.
67-75 A-Body Core Support Stiffener
Yup. Autozone is running a 20% discount right now, they will ship them to your door and you save a ton....
http://www.autozone.com/exhaust/exh...656_5281?fromString=search&make=&model=&year=