Go for it...adjust the valves, drain the fuel, change the oil (then change again after a couple hundred miles), flush the coolant and the brake fluid, then enjoy it. We purchased a euro R107 a few years ago, wouldn't have given it a second glance without the manual trans. It called to me
Did all the work your PO already has done. Its damn fun to drive. The next project (someday I'll get to it) is adding factory air.