OK. after you figure out the oil leak, take a look at the Dizzy. The clamping plate (moss# 543-135) is screwed/bolted to the block with the dizzy in it. The actual dizzy can rotate in the clamping plate and is clamped in place after you get the timing set by tightening a hex head bolt on the clamping plate. The bolt is in the horizonal plane, there is a "captive" square head nut on the other end of that bolt that does not turn as you loosen and tighten the clamping bolt. The only thing that will limit the rotation of the dizzy when you do it properly is the tachometer cable in the clockwise direction and the vacuum retard unit in the counterclockwise direction. Your sweet spot should be pretty close to the limit of the clockwise direction. The tach cable keep you from overdoing it.
From reading your post, I'm thinking you are trying to adjust the timing by turning the dizzy while it is clamped tight in the clamping plate and then trying to line up the holes to mount the clamping plate to the engine. That won't work. Bolt the plate tight to the engine and keep the clamping bolt loose so the dizzy will rotate but not the clamping plate.