Where is the oil plug for a 1986 goldwing interstate?

With the bike on the center stand, right side ( foot brake ) look under and in the rear of the engine. There is only one bolt in that place. Filter in the front casing with the ribs on it. There is a boss on the casing that fits the two lines on the block. There are two 0-rings to change, comes with the kit, watch how it comes apart, there is a spring and washer in there with the filter. Takes 3.2 Liters or 3.4 U.S. quarts. 20w40 Motul is good.