Lots of oil in plenum, no power in reverse
 

hey there, sorry to post a new thread but i havent been able to find anything about my specific problems.

94 chevy blazer 4.3 vortec w vin
no computer codes

things ive replced:
upper and lower manifold gaskets
spider injector, fpr, and nut kit
plugs, wires, cap, rotor
fuel filter, pcv valve
cleaned egr valve

i had to remove the lower manifold to replce the nut kit. the first time, i screwed it up and was getting antifreeze in my oil. did it again and think i did it right this time. replaced the oil and filter and drove it for a while. it will shift into reverse and move back on its own a little, but when i hit the gas, it will not move and has no power. in drive, it seems okay, except for the sputtering and lack of power uphill. i sopped up all the oil in the plenum and drove it for a week. ripped it apart and it had lots more oil in plenum and even some in the egr valve port! this cannot be right. if anyone has a clue what this could be please let me know. im about to drive this p.o.s. into the lake!!!

i just found out today it also is leaking from the water pump, so i'll have to replace that too. penty of time to work on it without a job, but not alot of money to replace parts. one thing we were thinking was possibly O rings or seals? im no mechanic, so if thats the prob, then i might just have to junk it. thanks in advance.