best hi flow ex manifold/drivers side

good info & actually I have one of the early large port magnum manifolds but it slightly touches the top of the steering box to where it will not seat flush to the head ex ports & I have already slotted the box mounting holes so I could lower the box (& a guy posted that this would affect bump steer (dont know what that is, I need to Google it) but handling on the circle track is everything. I could raise the eng a hair but the low profile aircleaner is very close to the hood. I could maybe hammer the center of the hood out a bit where the air cleaner is to gain some clearance then raise the eng (sounds like a good plan). I could lower the k member to lower the whole shebang but that might affect steering even more than lowering the box but that's way too much work. I'm thinking if i can grind the bottom of the manifold & maybe grind a very slight bit off the top of the steering box that that might do it but it feels risky. On a side note I remember a vid from way way back where the guy put some battery acid (iirc) in the manifold & let it sit then dumped/rinsed it & the CC capacity was significantly bumped up. this is where I'm at so far & the racing steering column is a skinny shaft. RR EDIT the magnum mani I have sure looks like an excellent piece but I there is a mani that will fit as is it would sure solve this pressing issue. MORE EDIT I just perused the thread mentioned & professor Fate that is dynamite info, thank you!