Ok let me also add that I had to change the oil filter after initial fire up from a long filter to a short filter to accommodate the exhaust system from TTI exhaust and the oil filter was 1/2 full... So I believe some oil is going somewhere..
If you had no oil, you would not have gotten this far. But it certainly is not adequate.
I'd get an oil pump drive hex shaft (you can make one from a piece of 3/8" steel rod) and a drill and spin the pump from the distributor hole; you pull up the gear and oil pump shaft that is down in the distributor hole to get to the oil pump drive.
When you get this gear and shaft out, inspect the hex on the bottom end of this shaft; that is what engages an equivalent hexagonal hole the oil pump. See if the corners on this hex on the shaft are rounded off; that would cause the oil pump to not be properly driven. If this is rounded off, it needs to be replaced and the pump replaced too.
If this is good, then use the hex drive shaft and drill to turn the pump with the drill at about 1000 RPM (600 minimum). You should see good pressure (like 30-60 PSI cold with 10W30); if not, then the next step is to start an inspection with the pan off.
BTW, what filter part number and brand did you put on? We need to be sure it is the right one.