Stumbling Slant --what is left??

All you gotta do is use a piston stop and remark whatever you got to TDC and adjust from there. if the 170 has the marks on the other side, just remark the tab. This is just to make sure the cam timing is legit If its not on the original balancer, it may have slipped (its ring is only held on by bonded rubber) or not slipped but shows the cam jumped a tooth if the marks no longer line up.