I did this recently by warming the body with a hot air gun and then tapping a rod through the screw holes underneath bit by bit and alternating the hole.
The block is a very tight fit so care is needed to keep it moving squarely, and I ended up with slight damage to the threads, which was easily fixed by running a tap down them(2BA I think they were).
If I was doing it again I think I would make up some long shouldered screws and use them to drift it out.
Just a bit of advice.....it is not easy to get the block back in and aligned perfectly with the Venturi as there is no location peg or screw as on a Monobloc
...compounded by the tight fit of the two parts, I spent a lot of time on mine and I still don’t think it’s as well aligned as it was before I started......and I only had one to do!