I didn't really read why you need it but, this is the least resource using way to PandA.(Also, one of the originals, for all you history buffs. You used to only be able to get the preview page from an AMT HIT search. So you'd get the preview link[the "p"] and add "and accept"[andA] to the URL making PandA)
https://chrome.google.com/webstore/detail/easy-auto-refresh/aabcgdmkeabbnleenpncegpcngjpnjkc
Easy Autorefresh. Put the accept url in the bar at the top of chrome. set easy autorefresh to refresh that page every few seconds. Ezpz. Wouldn't run to many or, you be back to taxing your system. If you're already using MTS, HitFinder shouldn't carry too much more overhead though.