I see you have a tranny temp gauge, how hard are the to install?
I useta have that gauge IN the ashtray, couldn't find the pic in time to post.
Gauge proper is easy; power, sender wire, ground. Some folks put the sender in the tranny pan; for ease of install I've always put them in the cooler lines. I try and get the hotter one, i.e. the one going INTO the cooler.
The sender is a bit harder, but I've done it on enough trucks now (three, four, I forget) that I have it down ... use the tubing cutter to cut out an inch and a half or so, splice in the compression fitting tee that B&M sends you, and tighten it all up. Fit in the sender, run the wire through the firewall, etc.
On my '74 K5 I did my own setup, using a factory water temp sender and a factory water temp gauge (upper left):
On the other trucks I just used the B&M kit ... yeah, it costs a bit more, but it's easier than sourcing all the parts at the hardware store and screwing around. For you as a relative n00b

I highly recommend the kit:
http://store.summitracing.com/partd...&part=BMM-80212&N=700+300222+115&autoview=sku
-- A