Everything I've read about this repair begins by bringing #1 piston to TDC on compression stroke and aligning the line on the crankshaft dampener with the index mark on the plastic cover secured to the block, at which point the larger of each of the two camshaft flange holes should oppose each other facing inward to engage the setting tool. If I do this on the unit I'm working on now, IT IS # 3 CYLINDER AND NOT # 1 at TDC ON THE COMPRESSION STROKE which lines up the 3 reference points. The camshaft flange holes align perfectly with the setting tool. With # 1 on compression @ TDC, the pulley mark is around 4:00 and the camshaft flanges are nowhere near where they could engage the setting tool.
In perhaps 100 entries on 3 Audi forums, I found only one reference to the possibility that Bentley (among others) is mistaken about cyl #1 as a reference point. As a rough confirmation, I pulled all the plugs and replaced each plug holder in the heads, sealing the holes with the rubber dust seals and turned the crankshaft quickly by hand w/ a 1/2" drive ratchet and 24mm 12 point socket. Each holder was blown out by compression as I turned the engine over. ANYONE ELSE NOTICE THIS ABOUT STARTING FROM CYLINDER # 1? Pls advise. Finally, I found a short 1/4 drive extension bar works well as a crankshaft holding tool in the hole on the driver's side of the block. If the only purpose is to hold the crank while removing/reinstalling the belt drive gear bolt, it works just as well as the special tool. Thanks for any replies-this #1 reference point issue drove me crazy. The consequences of incorrect cam timing are scary, especially with an old beater like mine.

 

Bentley is wrong - the index cylinder on the AHA motor is #3, not #1 (done the job already and know from experience). What you'll also find on the AHA (and the ATQ for that matter) is that with #3 indexed at TDC, compression stroke, the cam locking tool is entirely unnecessary. When our group did an ATQ Passat, we found we'd have had to whack the cam sprocket with a hammer to get it to rotate - positioning the #3 cylinder at TDC-c leaves the cams sitting in such a position that they don't try and rotate on you.

A hint from experience - when you put the new belt on, wrap the crank sprocket first, then up over the tensioner and around the driver's side cam sprocket, then over to the passenger side. We initially did it starting at the crank and moving to the passenger side, but found that doing the driver's side first was easier to keep the belt tense enough that it went on without skipping teeth.

But yeah, the Bentley is wrong - index the #3 cylinder and you'll be set up perfectly. Take that to the bank.