Information on a 340 for my 69 dart

i'm going to start looking for 340 stuff to swap out my225
want it to look 100% oe but not worried about date codes or stuff like that
i guess 340 were made 68 to 72 is there any thing i should look for (72 better then 68 ect.)
not going anything crazy want it to idle nice /stock exhaust /stock air filter
are all the sb sub frames the same (or do i need only 69)
i know its a lot to ask but i do see on fb market place stuff coming up and if something is local i might jump on it
is there something to stay away from
i'll start read threw the forums
thanks paul

I would get a 68-72 V8 K frame, 7/8 minimum torsion bars, 7/8 minimum front sway bar, lower control arms with sway bar tabs, and HD rear leaf springs. Start with a 318 short block (some early, 67-68?, blocks have very thick walls), get pistons to give you about 9.0:1 compression and run a high pressure oil pump and windage tray, Redo a set of 340 or 360 heads, next comes a 68-69 340 intake and AVS carb, get a curved distributor and electronic ignition kit, run a factory 340 cam and valve springs, run 68-70 340 exhaust manifolds and factory exhaust for a 69 Dart. You will also need good brakes (at least 10" drums), a 904 trans, and a HD rear end.