318 small oil leak

I chased a leak for a few days once. I ended up cleaning the motor at a spray wash and allowed it to dry, then I went under and used a spray bottle and a bottle of talc to dust the motor, all around the pan rail, uo front and across the trans bell. I let it idle for about 30 minutes and shut it doen. I looked at it a few days later and sure enough I found the track clear as day. It was the friggin oil sender, dripping down the trans seam to the inspection plate. You could do the same (and far easier) with some fluorescent oil marker dye and a UV flashlight. That works pretty good in the dark. Points to look: valve covers (especially cast, over an after market intake) front and rear intake seals, oil sender..?