[v8volvo]

You don't really need that much torque. The really key thing is making absolutely sure that the mating surfaces are super clean and dry. If you really get them cleaned up well, they hold just fine without all that much torque.

No need to break out the sandpaper, just carefully wipe all the oil away with a clean rag, make sure the rear cam seal is not leaking, make sure you use the good 1-piece neoprene valve cover gasket to ensure the valve cover won't leak everywhere, then put it together. I use just a clean paper towel to clean the surfaces then wipe down with alcohol or brake cleaner, whatever you prefer, to ensure everything is perfectly dry. I clean the bolt threads with a brass brush, then lightly oil the threads with synthetic motor oil. I also lightly oil the contact surface between the bolt head and the thick washer that goes between it and the cam pulley. By doing all this you ensure that all the torque you apply goes towards achieving max possible clamping force between the pulley and the cam, rather than fighting against friction. That way you can achieve plenty of squeeze where you want it without having to put a ton of torque on the fastener.

Make sure you have a counterhold tool to hold the sprocket with as you tighten the bolt -- you don't want the front timing belt doing all the work of holding things still while you apply torque, it is not good for it. The torque you are able to apply with a box end 19mm wrench will be enough to hold it if everything is clean.

The tools you really need for this job are the cam counterhold (9995199) and the crank counterhold (9995187 or 5188, I forget which). These are the essential tools that you cannot do the job without -- you need them to achieve sufficient torque on the crank bolt and to tighten the front and rear cam bolts without hurting the main belt and disturbing the engine's position. Rotunda Tool sells both of these tools. You also, of course, need the cam locking plate and the pump timing tools (dial indicator and holder), but you can make do with the VW style units on that front if that is what you have available to you. They aren't as nice as the Volvo ones (require removal of the rearmost valve cover studs for using the cam plate, and removal of the vacuum pump for using the dial indicator, both of which are not necessary with the real Volvo tools)... but they suffice to get the job done.

Don't forget to unhook the cold start device when you are timing the motor -- and also take the opportunity to ensure that the CSD is operating properly, giving full travel and release, etc while you are in there.