I am going to replace the hydraulic valve lifters on my wife's '94 960. I have all the parts, but my mechaninc friend at the dealership who was going to loan me all the special tools has just moved on to another dealership out of town. Now I am faced with making some of these tools myself to do the job.

I'm figuring that the tool that threads into the spark plug holes to push the top section down against the valves is probably a 'must have' to avoid any thread stripping in the bottom section. I think I can make a good facsimile of this tool pretty easy as I have access to a mill & lathe & basic machine shop stuff.

Now, what about the camshaft locking tool that goes in the back? I'm figuring to start the job with the position of Crank @ TDC on cyl 1 on power stroke. This should line up marks on Cam Pulleys to the basic set position. If I do this, and mark the Exhaust & Intake cam pulleys & cams so to not mix them up, and also to note the orientation of the three holes on each of the cams, then can the job be done without the cam locking tools? Any problems with laying the cams in the lower cylinder head section vs clamping it into the top section with the locking tools as shown in the Volvo manual?

Now the drifting tools for putting in the front & rear cam seals are tools that I think I will have to make on a lathe, and they should be pretty simple. Do both of these tools use a screw to thread into the camshaft to 'pull' the seal into the cylinder head? The clearance in the back is pretty small and I would think that this would be necessary in the back, but the front could probably be just tapped in.

The crank locking tool appears to me to be a convenience, but not a necessity. As long as the cams & the cam pulleys don't get mixed up, and the orientation of the trigonal hole pattern on each of the cams is correct with the pulleys, then there should just be the small error in cam positioning due to the slop in the clearance holes in the pulleys. If I do all this and align the timing marks on crank & cams, then all should work. Am I missing anything here about the utility and advantage of the locking tools?

Have I missed any other special tools needed for this job?