Hi All (Happy New Year)

Been a while since on here. My problem is end of last year I replaced the stem seals with with GM ones. Last week end I started it up. Now when the old ones were on there I had a little bit of smoke but not much. But since changing them I now have loads of smoke? The stems do not have any grooves on my Astra MK3 1600 16v Eco Tec 1995 model they are smooth. The only thing I can think of is the seals have come up again. As oil is getting passed again looked down inside with out taking it all apart it is not just oil damp there is a puddle of oil down there. As i said there is nothing to keep them in place? Brother is on about super gluing them in place. He has a 1994 1400 he replaced his they are fine as his stems have a groove? Bit confused why mine hasn't got any grooves to hold the stems in place?