1. Rear timing belt (is it called cam belt in Europe?) cover in my 01 Cadillac Catera 3.0 has marks, so there is no reason (?) to use belt gauge to check position of cam sprockets.
2. Manual says to check timing belt tension. Why do I need to check belt tension, if tensioner has marks showing right tension?
3. How do hold cam sprockets w/o special tool?
I would also add, that even if your belt had timing marks, they are fairly useless anyway, because each bank of cams are adjusted as a pair, via the eccentric adjusters on the corresponding idler. So the cam wheel marks can be on the belt marks, but the cam wheel timing can still be way off. Hence the gauge in the kit.
It's not a case of simply getting the teeth to line up, like on most cam belts. You have to adjust the cam timing on cams 3 and 4 (to within fractions of a millimetre) then once correct, only then can you do cams 1 and 2. Hence the )( shaped gauge to check it, a cam locks to stop the cams spinning out, and the crank lock to guarantee crank position.
Without the crank lock your pissing in the wind before you even start.