New guage cluster install:suggestions needed

[Bullett]

I have bought a new guage panel and guage set to install into my 62' SWB fleet side.
O.k., to get to the painful point, not really sure how to wire up the gauges. And also, there are some very small colored light bulbs that I am not sure of their function

Each guage has 3 posts on the back side, 1 being the ground post, 1 being the sending unit post, 1 being the ignition terminal post. O.k., as far as the ground, is it o.k. To run a new ground wire from somewhere handy on the frame to 1 of the gauges and then just loop from guage to guage? As far as ignition terminal post, where is a good place to pick up power for this post? And also, can you loop from guage to guage? As far as the sending unit post, is there only 1 wire that goes to each sending unit? I took a pic of the sending unit I have now, on my fuel tank sender, there is 1 wire that goes to the fuse block:
Underneath this wire connection, there looks to have been another wire connection that went somewhere, what would that connection have been for?
Next question: all the gauges have a light connection terminal, where do you get the power for these?
Also, there a several very small colored light bulbs that came with the kit, where do they go? It says nothing about them in the manual.
Next question, what should I do with all the old wires and light bulbs that went to the factory dash?
I know, lots of probably stupid questions but I want to do this once and do it right and am sure that you folks could save me a ton of time and headache. Wiring has just always been my Achilles heal. Thanks for any info.