GM-GMC: Chevy Blazer misfire, chevy blazer, pressure sensor

Question
QUESTION: I have a 98 Chevy Blazer 4.3L V6 engine. I have been having multiple problems with it. Mainly misfires. Recently I had gotten the code which says that my pressure sensor was running to rich. So I changed the MAP sensor and it quti misfiring as bad. Then I didn't drive it for a day and a half and it poured for the day and I try to go and start it and it didn't start. Brand new battery so it wasn't that, and it wasn't taking a jump. So Weather became better for a couple hours the next day, I pulled the plugs and cleaned them and made sure the plug wires were in proper order, 1 and 3 were backwards, so I moved them back. Tried starting it and it took a bit for it to start but it finally did. So then it was misfiring really bad, so I replaced the fuel filter, still misfires really bad, worse then it did when I replaced the MAP sensor. When sitting at idle, whether in gear or in neutral it shakes and I mean shakes bad. So then I go and press the gas and it has a hard time, unless I really gun it and go over 3000 RPMs. It misfires worse when its wet. I can not figure out why. I did a tune up on it a year ago, plugs, wires, rotor, and cap. Misfired 3-4 months after doing this, which was right after winter. has new purge canister, fuel pump was replaced last year. Also has a 2" body lift on it, so plugs are exposed to wetness. I don't really want to start guessing at whats causing the misfire and replace things one by one. I don't have alot of money like everyone else and fix it in one shot. So why would it misfire more when it was raining or wet?

ANSWER: My guess is that you have a plug wire shorting out.  Try this...at night (in the dark) start it and run it and look for little blue arc of electricity jumping from one or more of your plug wire to the engine or any other metal part they are close to.  If they are arcing, replace the wires.  It would do this more when wet because the water helps conduct the electricity.  
Hope this helps.

---------- FOLLOW-UP ----------

QUESTION: So it wasnt the plugs because I put new ones on before I got your reply. So I went and replaced the ignition coil and the ignition module and it didnt work. So as I was driving later that day it quit missing and the CEL went off. So I started it up today and drive and it starts to mis again. As Im driving home the car gets worse and the CEL turns on. I dont know what to do any more. Help.

Answer
Did you try what I suggested with the wires or just dismiss it becuase you have replaced them before.  What you are describing to me sounds like an ignition misfire, especially due to the fact that it is worse in wet weather.  Double check your wires and your cap and rotor, make sure there isn't corrosion built up on the tip of the rotor or the contacts inside the cap.
Thanks for the good review!!!