New sol-vac came in. Woo, I have high idle again!
Also did a parts inventory and it turns out that the heater core bypass I salvaged is not actually needed on my car. It's only needed on models with Air Conditioning and it's a VERY common failure point.
So it was a surprise when I found people pretty much throwing parts at me in exchange for the thing, simply because the diaphgram held a vacuum, so it's been refurbished.
Also had the front hub actuator tested when the car was in for seals. They confirmed that it operates with relatively little vacuum, however the transfer case actuator still will not pull it into or out of 4WD. They were not being billed to service the 4WD so it looks like I'll be spending more time underneath testing all the vacuum lines for a leak.