I still think Campbell can play tackle. He's got traits and instincts that Jackson and Raimann didnt/don't have, especially coming out. Not saying he is guaranteed to be a tackle. If arm length is the only true concern(other flaws are correctable), and guys with similar arm lengths can make it work, why can't Campbell?
Membou has entered the discussion but I wouldn't prefer it at 4. Campbell and Membou both basically displayed at the combine exactly what we expected. I heard it mentioned today on a podcast - don't count it twice. If you expect something at the combine but you already factored that into your evaluation, you don't count it again. We expected Membou to be athletic and powerful. We expected Campbell to be athletic but with short arms. I dont think your evaluation or placement should change much because they did what you expect. If Campbell had 34" arms, he forms a clear top 3 with Carter and Hunter. He's already been downgraded because we knew his arms were short.
Just my personal opinion, but Campbell is still OL 1 for me, although I know others feel different. Still hoping for a trade down. Especially if one of them is the target and you could get one at 6 or 8.