Here are photos of some of my most-used tools. I find angle-tip pliers and tweezers more useful than straight tips. The JIS screwdriver comes in a set of five. It's made by Hozan and available from Amazon. The Wiha tools are also available from Amazon, except the Pozi drivers which I had to order direct from Wiha. In the process of ordering the Pozi drivers, I discovered that Wiha sells all kinds of cool tools and they have a good bargain/closeout page. A 12 watt soldering iron is the right size for most work inside a locomotive - you don't need anything bigger to solder components to a board.
Right side: Small LED flashlight,12 watt soldering pencil, JIS screwdriver,assorted Wiha Pozi-drive, Philips, and straight screwdrivers. Left side: Cross-lock heat sink tweezers for soldering wires, large angled tweezers, fine point curved tweezers, screw grabber, angle tip needle-nose pliers. The bench mat is made by Ransom for gunsmiths. It is made of rubber and has a rib around it and compartments at the top to hold parts.
Here are two kinds of grabbers. The one on the right is the one you want for setting screws. It has three prongs that open wide. The one on the left has four prongs and doesn't open as wide. It's for nuts and small parts.