For the fuel system, you can use a fuel pressure regulator to drop the EFI fuel pump's 40+psi down to just 7psi for the carb and return the rest back to the tank. I'd upsize the return fuel line to at least the same size as the feed line, if it isn't already, to avoid any fuel back pressure issues.
The 4L60E (the "E" dictates "electronic") would require a computer to tell it when to shift. You can buy stand alone control modules to serve this purpose but they are stupid expensive. By expensive I mean you could swap out for a TH400 for cheaper.
EDIT: Just read that you have a 700r4. This depends on what year you have as the later years of them went electronic. The earlier years were non-electronic, mechanically shifted but also weren't as strong.
1993 Camaro bracket car
2002 Tahoe family/tow rig
2006 Altima daily