I wouldn't even try running port injection on a TBI pump. If you don't want to do it all at once then change to a TPI pump first since the TBI system will still work fine with it.

You could get adapters to connect -AN line to the front of the hard lines on the truck where the braided lines to the TBI start. Then, just go from there. I took the TPI connectors and braided TBI lines to a local hydraulic place and they crimped the ends onto the braided lines.

As for the booster, it's a non-issue. The steel line is on the engine side and will be removed when you pull the TBI intake. So, just run a rubber hose from the booster to the vacuum port on the TPI intake.