just got a 1988 1.2 gamefisher I think it's a "tanaka" i tried to drain the gear oil but it only has one plug which is for both drain and fill and it's real small problem is i does not drain that good and for some reason i don't trust it when i fill it up "not sure if it's filled all the way.Has anybody taken off the gear housing cover it's got 2 bolts would like to take it off but want to make sure it's ok also is there a gasket between the cover and gear housing and is there an easy way to fill this thing up the hole is very small thansk