303 507 crank locking tool £30 !!!

Do I have to use this to set up the timing ?
can something else be used ? (5mm drill etc ?)

I am half way through head gasket replace on focus st170 2002.
next step is to release the cam belt tension so I can remove the cams and get to the head bolts, I have the cams locked already and engine is at tdc.

cheers,
Jamie