ATD, Nesco & KD Tools have some of the exact same things I can get off the Snap-On and MAC trucks. I'm not saying everything should be bought from your local autoparts store, but there are some products that you would be able to save money on by doing so.
Your theory should work if you're able to hold everything still. I broke the crankshaft pulley bolt free by using the starter method though. There's this tool called a spark plug piston lock made by LTI Tools...part# LTI 865. Use that tool and you shouldn't have a problem trying to get the crankshaft pulley bolt back on.