I would just save your money and fish an LT1 or an LS1 out of a wrecking yard somewhere. Yank the 3.1/5 speed combo out of the 'Maro and sell it. Use the Buick for a daily (if you don't already have one) until you get the project finished. If you already have a reliable daily driver, than sell the Buick too for some extra cash. Otherwise, this could turn into one of those "lost interest" projects due to parts chasing and problems.. Or if you REALLY want a turbo car, then yeah, try an LC2. Otherwise, just stick with a V8 swap.