1995 GQ RD28 Blowing lots of White/Grey/ touch of blue Smoke,

My son bought it with compression coming out the radiator thinking just a head gasket. Later finding out cracked head so purchased A new head and VRS head gasket kit and spent the weekend changing it with his mate. Blocked the EGR at both ends as pipe to manifold was broken. Now after all that we started it and it's now Blowing lots of White/Grey/ touch of blue Smoke like someone has a smoke machine going. After a long while it lessens but not totally gone. Still a constant puff even when hot. So need help. It wasn't doing it when he brought it home before they put the new head on.