that is the bead of FIPG someone put on the oil pan gasket when it was replaced once. There IS a plate behind the cover, but I think the bead we're questioning is the pan. if it's down and not going anywhere, you could order a new 1 piece gasket and drop the pan. OTOH, if you think there is a [possibility of the timing PLATE laeking too, just bite the billet and go for it now. you will need to remove the pushrods and side cover and lifters and cam and crank gear to remove the timing PLATE. at that point, if there is anything inside you want to check out, you may as well do it. Wash that sucker down and be very careful when IDing your leak(s) point(s)