Just use a round drill bit a 1mm larger than the tang and drill 2 or 3 holes so they overlap, file out any protrusions. The front bolster covers the hole created, but the front bolster needs either milling out, or drilling with smaller holes than the tang and filing out into a square hole just big enough for the tang to fit into. This bolster will keep the blade alligned in the main handle block while the epoxy cures. Then to be extra secure, just drill a hole through block and tang from the side and glue a pin in.
