headers/exaust

I'm trying to find a nice cheap pair of headers for my stock 318, I saw the ones on summit and was wondering if I'm going to have to remove my power steering box to get them in. my other problem I have is would they limit me to getting my oil filter there? also what size of pipe do I need for it? someone said 2.5" would be best but is that too big? any help would be great
You won,t have to remove your p.steering box,but will have to drop your centerlink(draglink)to get the driverside on.Oilfilter shouldn,t be an issue.You can run 2 1/4 or 2 1/2 inch exhaust,whichever you prefer.The 2 1/2 inch will be louder.Good luck!