From what I remember of the Ace pear, it was quite sweet compared to many other pear ciders, and for this you'd probably have a bit of an issue in coming close to it unless you were kegging and force-carbing. I'd say find yourself some pear juice (easier said than done) then ferment with a clean American yeast, us-05 would work great. After 2 months or so, rack it into secondary and wait for another 3 months. At that point taste it and see where you are at with the acid/tannin level, and adjust with acid blend/tannin. For the sweetness you'd have to use a unfermentable sugar (lactose/splenda/stevia/xythol) unless you are kegging, in which case you'd be able to kill off the yeast, backsweeten and force carb.
Primary:Russian River Redemption clone, Kelly's Melomel, Graham's English Cider 22-23
Aging:Public House Dry Stout, Procrastination Porter, Mr. Brown Ale, Westvleteren 12 Clone, Mead, Duvel Clone, Graham's English Cider 6-21, Belgian Draak Strong Ale, Fig Melomel, Acerglyn, Restorative Tonic Metheglyn