Help with a no crank/no start on my imported 2500.

I have a 94 Ram 2500 Regular Cab that was imported from Mexico to NC.It has the 360 motor with a 4 speed manual trans and 179km (112k miles).

I just put belts on it (does not have a serpentine belt) and changed the oil.After finishing the work it won't crank.I drove it into the garage and an hour later it won't even turn over.Seems like the starter has failed or is not getting power.Dash lights and all are working and I have fully charged the battery.I do have constant power at the relay plug,tried different relay, and the hammer trick didn't work.
Can anyone point me in the right direction of where to Start trying to find the problem?
My first guess is the starter.Is there an easy way to test it on the vehicle?

I have a fairly decent knowledge of vehicles but troubleshooting electrical problems isn't my strong suit.

Any help is greatly appreciated.

My truck has a brown wire coming from the starter, and its below the big fuse box under hood. If you disconnect that wire, there is a connection right there, hook up a remote starter swithch to it and pos bat, it will turn over so you will know if the starter/solenoid is bad. If it turns over, probly in the switch, or something else.

I got some time last night to work on it.
I ended up taking the starter off and bench testing it.It works.I switched the relays around again but still not cranking.I'll follow the smaller wire off the starter and see what I can find this afternoon.Maybe the signal wire is the culprit.

Got it figured out and the truck is running now.Turned out to be a broken ignition switch.I guess it wasn't making contact in the start position.Installed a new one from Autozone and it fired right up.