Actually, with a higher stall converter it would be nice to keep the lockup function. Makes it much more street friendly.
That 3000 stall converter in my brother's '81 is kind of annoying when your cruising at 55-60mph. With the TH-2004R and 3.73 gears, he's only turning around 2000-2200rpm so the throttle response is pretty dismal since the converter isn't close to its stall speed.
You may be fine if you go that route but like I said, Art Carr changes the fluid routing in their transmissions when you do this. Don't know if that's really a necessity or not. I think the purpose is to try and help keep the transmission fluid cooler.