Pulling tall ratios with a stock engine is hard on the mains. 3.54 and O.D, I'd absolutely want a souped up or "touring" engine. With all of these O.D. plans the ultimate decision is how fast will you actually travel? How's the brakes? Suspension and shocks in good shape? You've got a bunch of knuckle draggers on the the roads with you these days and none of them care about you or your precious old A, and that also includes any precious cargo you're taking along. I wonder how hard you can jack the wheel at 55-60 without losing control. I guess my point is that you should consider all the facts related to higher speeds in these ol girls. I know my truck needs some suspension and shock work well before I consider anything speed related. Some licknob texting, coming at you on a 2 lane, big deep ditches on both sides, not many places to go let alone support any form of evasive maneuvering. It's happened to me twice in 2 seasons and it will indeed tighten your pucker string to the limit. Just sayin...