Welcome to the forum and glad to see you are keeping another GEN1 on the road. I recently went through the same process when I replaced the motor in my 89 LWB 3.0L. These forums, especially the archives are an excellent source of information. Be sure to check out www.mitsubishilinks.com
for access to the full GEN1 Service Manuals which are much more detailed than the Haynes (plus you can reprint them often...)
To answer your questions:
1 - I don't believe that the vacuum line at the bottom of the canister attaches to anything. I believe it is a drain, but I will check when I leave work tonight. From what I recall, there is only (1) hose that crosses over from the inner fender to the intake and that connects to the metal lines on the side of the upper intake.
2 - I believe that the ground wire you are referencing attaches to the block at the mount for the AC compressor.
Be sure to replace the crank bolt and washer with the updated one from dealer. They were problematic.
I've been working through my GEN1 as it is my daily driver. I still have some work to do on the suspension and driveline, but it is getting there slowly. I should get a Google Drive setup so I can document & share pictures easier.