The 700 requires no vaccum. What it does require is a TV cable and the proper brackets to make it work correctly. If you are using a Q-Jet, make sure you have the proper factory brackets. You will need to transfer the throttle arm from a factory 700 equipped q-Jet to your existing carb.
Read this:
If your using a primitive Holley or inferior edelbrock () there are aftermarket brackets for pretty much any model carb.
Whatever you do, make absolutely sure the TV cable is installed and adjusted right. Close enough won’t work. You will burn up the trans on no time if it’s not right.
As for the speedo, does your 700 have an electric speed sensor or is it set up for an old school cable? If it has cable provisions, I’m you just need the correct gears to make it accurate. If it has an electric speed sensor, you will still need the correct gears, and the speedo hosing and clip. Remove the extension housing, use a bearing splitter or gear puller to remove the speed sensor tone wheel, install the correct drive gear and clip, remove the speed sensor from the extension housing, and install the correct gear and housing and retaining bracket.
Use this chart to calculate the gears you need:
Use this TCI Auto Speedometer Gear Calculator Formula for any GM, Ford or Chrysler vehicle. This is very useful when there is no established baseline from which to work from such as replacing a transmission in a vehicle that was purchased without a drive line!
www.tciauto.com
As for the lockup converter, the absolute best, no driver input needed setup is make by Bowler transmission. The kit includes a new solenoid, pressure switch, brake switch, and control module. Once the trans goes into 4th gear, 10 seconds later the converter locks. Hit the brakes, it automatically unlock and relooks 10 seconds later. It’s a pretty slick setup, but it’s also kinda pricey at 190 bucks last time I bought one. You can do it much cheaper with a little wiring, it’s been discussed on this forum many times.