I'll have to partially disagree with gray ghost. Most shops (even many tranny shops) just don't get it on the TV cable adjustment. They are used to factory assembled vehicles, not old trucks with late model components. Since your intake and carb were never intended to be used with an overdrive, the bolt holes for the bracket are probably not in the right location, and the carb's geomitry isn't right for the rate of pull that the TV needs to ensure correct line pressure.
I highly recomend getting the kit from
www.bowtieoverdrives.com
You have heard correct on the importance of the TC vable's settings. Even if it feels right, if it isn't dead on right, it'll be worth it's weight in scrap after 10,000 to 20,000 miles.
The physical part is pretty much a remove and install. You'll need to pay attention to the converter though. The 200 4R was installed on engines other than Chevy in the GM lineup, and some of the makes had flat flet plates, and some had raised pads where the converter bolts up. You'll want to use the right converter for your aplication (chevy small block flex plates are flat if memory serves... been a while for me)
Your shifter may or may not be OK. many aftermarket shifters were set up for either/or, look up your model number and find the listed aplications.
You will also want a way to lock up the converter to prevent excesive slipping. A toggle will work, but is not recomended since it will not unlock when you have to jab the brake pedal in a panic stop. This will stall the engine, and can cause isses like cracking/shattering the flexplate, and/or breaking the bolts that hold the converter to the flexplate, or even the bolts that hold the flexplate to the crankshaft. U-joints can take a seriouse beating in this type situation too. Think of driving a stickshift at 70 MPH and locking up the tires without hitting the clutch... a lockup will make the connection from the tranny to engine even stronger than a stickshift.