I Have An 1987 Ford F150 That Needs A Tune Up And More?

The 87 Ford F150 is a 2WD 4.9L in-line 6 manuel trans with dual tank. I changed the oil and oil filter, replaced the wiper motor with used part (mine was slow and stopping), new wipers, replaced the power booster with used part (mine had vacuum leak)(also this one is a little bigger then old one was), replaced bad seal in RR axle and added new gear oil, replaced 90% of brake lines because of rusty and broke when bleeding brakes (all clean brake Fluid now in lines), replaced center drag link (mine was egged and loose steering), replaced seals in steering for leaking, and added clamps to leaf springs (old ones broke or missing). I am not sure what else is need to do a tune up. I see and know of new spark plug wires and dis. cap. New starter and starter solenoid. The truck is running rich with black spitting out exhaust pipe. Have to change the valve cover gasket because of leaking oil as well as oil pan gasket. For oil pan gasket can i use the liquid gasket on it or buy a gasket? Please help me with my truck. How do i test the EGR valve also? Thank you!!