A very strong position for Hull. Of those I've seen play Skerrett would be my favourite. Rock hard, heaps of energy and a hard (but fair) hitter. A truly outstanding defender, he stopped them in their tracks head on but also pulled off some cover tackles that would be outstanding for anyone, let alone a prop. He was a key man in the trophy winning era of the early 80s who usually featured in the man of the match voting in the big games. Unfortunately a serious knee injury wrecked his career and he never came back the same player but at his peak awesome and one of the few players to get the Aussies respect. Not far behind for me was Karl Harrison, another real hard man and a leader in the Brian Smith revival era. But there's plenty more just covering those I have seen, Charlie Stone, O'Meeley, Mick Harrison (though his best years were before my clear memories) were among the very best but there have been quite a few others that have got the odd representative honour which shows they were more than decent Farrar, Tindall, King for example. And that's without the famous 50's pack which was before my time but I'm sure the old timers will have fond memories of Scott and Jim Drake and maybe more. Finally going way back to the 20's there's a guy called Harold Bowman who went on 2 tours Down Under, represented GB and England and played over 450 games for Hull - that looks real quality and service.
For Lee Crooks I would count him as a 2nd row for Hull as that was where the majority of his very best performances for the club came from. Over his career he no doubt counts as a prop but his most of his best games in that position were for teams other than Hull.