Couple of problems,need advise

I put in Corbeau GTSII seats in my 65 coupe. They seem to set a little high. Is it very hard to remove the seat platform? I might have to cut it down an inch or so. Also I bought an AC from Classic Auto Air. After I installed it, it started to get hot. 210-220. At Idle it is fine but going down the highway is when it overheats.I have an electric fan from Hot Rod Air. I live in Phoenix too. It seemed like the condenser that is mounted in front of the radiator is blocking some of the airflow. My system is very clean. I have a Griffin 2 row w/1" tubes. So I put on a Shelby front apron. Didnt help. Was running a 195 thermostat and changed to a 180,that didnt help either. What do you think? Also I screwed up when I changed the oil after the cam break in on my new motor. Changed oil the filter and didn't realize that the gasket from the first one stayed on the engine. Started it up,oil pressure was good. The lifters started to tick so I looked @ the oil press gage. . Zero pressure! Shut the engine down right away. Ran maybe 2 seconds w/o oil pressure. The oil blew out of the extra gasket all over the floor. I corrected the oil filter problem,wiped up all of the oil,refilled it and started the engine again. The oil pressure is good. How worried should I be?

I found the article from Mustangs Plus about the seats but I steel need your help on the other 2 items.