EPDP99

Hello all! I'm new here but have been searching for a while. I have a 88 lx 5.0 HO that a couple years ago I was having issues with. I'm currently trying to get ideas so I can plan these for the "getting it roadworthy" phase. I will be going through alot of things including draining and pumping new fuel through everything, cleaning intake, egr as well as changing all fluids. Recently before it went down it was just my fun car and not my daily driver. It had some oil leaks here and there so I did a gasket kit to fix those and shortly after that I installed an e303 cam with a 93 computer and converted it to mass air. Running a large K&N in a cervini's ram air hood/kit. I noticed at idle the oil pressure was way low but once on the gas it came right up and stayed up. Any ideas for a reason behind that? I took it off the road because it wouldnt pass emissions. Everything would pass except my idle hydrocarbons. they were 1213!!!!! that was at idle, runing at the higher rpm they were 131 of 220 which is still high from previous years tested. It does not have cats on it only shells( I know this will cause issues and higher HC counts but it has been passing like this for years). It never smoked except a very light haze on hard acceleration, didnt seem to have any misfiring or running rough, had good power. I replaced the cap, rotor, wires, spark plugs and ignition plug on the side of the distrubitor with no luck. I will be replacing the coil as well as plugs, wires cap again since its been sitting. Looking for advice on some things to check out before I get too involved. I would rather not pull the motor to get it on the road but if I need to I will.
Thanks in advance! I will try to post up every detail about the car its just been quite a while since dealing with this. This was my first 5.0 and have had several others including more modded than this but just hard to get rid of the first car...