Rats. Pretty far to go....I'm in Tampa...
I ask because I just converted my (different from yours) car over to a cold non-heated intake....heater works, gauges work...but for me to describe what I did is almost impossible.

As a general principle, all metal pipes need to be either capped off
or a hose connected to them....and with some luck there will be an even number and/or pipe sizes will be the same.

If all you did was remove the heater core, connecting heater hoses to Rang's u-pipe may be your best bet.-Bob