I have a 10 bolt rearend in my 69, I pulled it out last week to clean, paint and change all of the bearings. when i mounted it on the stand i had oil dripping from the spring perches welded to the housing,after i cleaned around the hole where the dowl fit in there was a hole all the way thru into the housing on both sides is this correct and if so how do you seal it,silicone? thanks ...

Sounds to me like the perch is pulling away and ripped a hole into the housing at the front of the perch.
This is a common problem and the only way to repair is to weld it, and if the perch is in bad shape have new ones welded on while it's out of the car.
If the oil is coming from where you say it is (dowel pin hole) it must have worn though and is not normal and will need to be welded.

IF this is right where the spring bolt-head fit's, it sound's like somebody drilled a mono leaf rearend so multi-leafs fit like stock and went too deep and through the housing itself!

????????????? What spring perches are on the housing?????????

Short, mono or tall for multi??

pdq67