rear tail and reverse lights

I have a problem with my old chevy s-10 with over 324 000 miles. The issue that i seem not to diagnose is that recently my brake lights tailight and reverse lights have rebelled againt me. For over 15 years i never had an electrical problem but now i am stumped. When i drive in the daytime all my lights operate properly but once i drive at night and i put on my running lights the problem starts. For one once i have the tailights on and i put on my left or right signal both signal lights blink dimly, than once i drive with the tailights on and i step on my brakes the reverse lights come on dimly and the brake lights go off while the tailights get so dim that they cannot be seen. What is wrong wiyh this old dog? Any help would be appreciated, Thank you all.