360 into 64

No need to ream them. Don't know what you mean there. They will fit as is. Not sure how hot your 360 is, but manifolds will work just fine unless it's a real fire breather. Dougs headers come to mind.....at about 850 bucks. Also Dakota 5.9 Magnum manifolds might fit....but are hard to come by. I think they were only made from 91-93 and only on the 5.9. I have read and heard they were on the 5.2 Magnum, but I think that's a mistake because I have pulled several pairs and no 5.2 I ever saw had them. They are 2.125" outlets, btw. Even the standard Dakota V8 manifolds probably outflow the stock 318 ones....but again, unless your 360 is pretty hot, the 318 manifolds will be fine.