dip stick tube hole

What's the best way of sealing up the sierra dip stick tube hole in the web of the block just below the fuel pump boss.
It appears thats where the oil leak is coming from ie my poor atempt at sealing it, which probably means exsessive blow buy preasure in the block???
Thanks
JP
It appears thats where the oil leak is coming from ie my poor atempt at sealing it, which probably means exsessive blow buy preasure in the block???
Thanks
JP