Dartin for Divorce

get something like THIS with all electric gauges. it's fairly easy to install and you can always go mechanical later if you think you want to. these are easy to hang from the bottom of the dash or A/C vent. also get a tach and you'll be set. check out ebay, you can find new old stock stuff cheep.
most? a lot? of the people here with automatic transmissions run an external cooler. either by itself or in conjunction with the one built into the radiator. if it already has one plumbed in great, but i'd deal with the reliability stuff first.

hope the wife and new kid are doing well