Our local aftermarket VW parts supplier (AVR Import Specialties) has made what looks like a giant open end wrench, with 4 holes for the harmonic balancer bolts. It is about 3 ft long, and provides enough leverage to hold the crank.
I'm assuming you're dealing with an AAZ diesel engine. Do you know if the crank sprocket has been pinned, or changed from 'E' suffix to 'D' suffix (TDI type)? Once you have the balancer off you should be able to check. If pinned, you should be able to see 1-3 holes arranged tight around the center bolt. If you don't and the suffix 'D' part number isn't evident, I would definitely pull the bolt and sprocket for verification. Then, either modify the crank to TDI fitment, or pin the sprocket. These engines are famous for the sprocket loosening, destroying the key(

) and keyway, along with valves and pistons.
http://forums.vwvortex.com/showthread.php?1598023/page1 will point you in the right direction for the pin mod, and anyone with access to a drill press, power drill, and decent drill set, should be able to do it. The particular write-up is dealing with the supercharged G60 (and there is no TDI type mod option for that engine), so don't go by the part #s. I don't feel that bearing rollers are necessary as pins. Just cut up some decent HSS drill bits and use the shank ends for pins, double or triple pinning the sprocket, as shown. Plus, using drill bits makes diameter matching a snap. A double or triple pinned std sprocket should be plenty strong. When I was a kid, I had a small two-stroke bike, with a taper-fit 10 pound flywheel, that would shift timing every time you 'speed-shifted'. We cured the problem by getting it on time, drilling a single 3/16" hole in the crack between shaft and hub, and inserting a small piece of 3/16"drill rod. Even when the engine locked at 4000 rpm, stretching the connecting rod, it didn't shift time. And
NO, I didn't make a mistake, the D comes after the E. There was another post referring to this, and the respondent made the error of thinking the E was after the D. He corrected his post later.