partsgirls 71dart/440 engine cast iron manifolds

haaay yall! i`m kind of an old mopar fan...i even think i kno quite abit about them! i was raised in the backseat of late 50`s n 60`s imperials...many old 392 hemi`s...we had other models too and i love them all from finned 50` to superspeedway wings and evrything in between! (i`m a mopar NUT) my Daddy knew tons of mopar guys, ones who worked for mopar dealers and the assembly plant. there were guys wrenching at our house or wherever we went and we went to the new car showrooms evry yr when new models showed up! so enough on that for now...the reason i`m writing...my question...my concern is that;
when i install (have it installed actually, i`m not doing it...i might break a nail!...giggle) this;
71 440 engine and 727 trans from an imperial in2 this;
71 dart swinger using the stock cast iron manifolds;
WILL THEY FIT?
WILL I BE ABLE TO GET STOCK PIPES?
i`m using a motor plate to install the engine. it seems much easier/cheaper than using a new big block k frame. i don`t know about using the stock transmission mount though or precise location for the engine...i know its a tight fit and will be backed up2 the firewall. i`m sure i have to get the driveshaft cut...i`m trying to do this on the cheap so thats why i want to use the existing cast manifolds and tentatively leaving the 6 cyl torsion bars (i am switching it to disc front brakes and likely a rear gear in the range of 3.91 to 4.10)...its for the street anyways, just more for looks than real go...even so it might pull mid 13 quarter miles on a good day with the wind at my back and blowing my fair hair as i wave off in2 the sunset on a beautiful day in the neighborhood...are u still reading?...lol...any advice will be most appreciated...love, Candy! (rock on mopar lovers!)