If you use Schumacher mounts (that were not made when I originally did my BB conversion in 1989) the engine will be basically a "drop in". The trans mounts to the exact same spot with the same mount as a SB or S6.
Most likely the least expensive option for doing a stroker is to use a 440 Source stroker kit and you know it'll all work together. Plus all the parts are way better than any stock piece, along with being brand new. I thought the kit price was a lot until adding up the cost of building a 440 using the original reciprocating assy. Turns out, the kit is actually a bargain and to be honest, was a big part of how it ended up being a 500" engine. I think their kits are now $2,250 to your door.
LOL, I almost felt bad putting the parts in an engine. Wanted to hang the crank and rods on the living room wall as art.
Almost felt bad putting the parts in an a
Headers MAY be a problem depending on budget. I've got Schumacher "Tri-Y" ceramic coated headers and they were not cheap but found they were worth every penny. Excellent pieces and fit like a glove with no problems at all. Of course, stock passenger car manifolds will work as well. The hi-po style (the kind that swoop up past the valve covers) will not even come close to fitting however.
Stock floor shift will work fine with the auto with no modifications. You'll have to use the Bouchillon throttle valve (kick-down) cable kit.
With a 383 you probably won't have clearance issues with the throttle cable. I ended up moving the exit point from the firewall an inch to the center of the car and an inch higher to clear the valve cover without having a sharp bend. Of course that also meant moving the gas pedal over and up the same amount which puts it in a sort of odd position in the car but I've gotten used to it.
For a radiator, I had a local shop (Glen-Ray Radiators, the place that makes the repop Hemi and BB radiators and p.s coolers.....) build a 3 row using the biggest tanks and side pieces that were available in an F-body. With the A/C on and 90 degree day, temp gauge rarely goes above 1/2 scale. If you use the 440 Source right side exit water pump housing, the lower hose will be on the correct side to hook the the radiator without running across the car from one side to the other. Mine was like that for years and it always bugged me.
Stroker Kits-440 Source