90? From the block deck? Think they are like 135 or something, wider. Honestly in that regard I've never checked. I've always made an even cut , if performance or blueprint..then I will cc chambers and if need be ,take more off one end or just open up a chamber some if that kind of deal.
I have encountered many older/early edelbrock intake manifolds , like ld340's ..to be tapered to one end. Many 90's and up edelbrocks seem to be too big and need cutting. The wieands all seem to be made to fit a basically stock engine, like every deck factory 'over' spec.