cam timing advice for first rebuild needed

Wow - Crikets??

Yes: Cam duration is always given in crank degrees. I suggest a degree wheel, a nice dial indicator and patience. I'd also suggest studying lobe center methods for setting the cams. You're at the heart of Ferrari engine tuning. This is where you get the "recipe" right for your engine and extract what was achieved back on the dyno at the factory. Off by a "little" (2 degrees), and further tuning gets fussy, more than that - real fussy. Wildly off ----- let's not discuss that.
Below is a quick internet find on cam timing. Most of this relates pretty well. http://www.motorcycleproject.com/motorcycle/text/lobectr.html

Also, I'd suggest checking out the Dino 246 shop manual, and the guys at Superformance know the Dino motor frontwards and backwards.

 

The cam opening and closing timing is listed in the manual in crankshaft degrees. You need to mount a degree wheel to the crankshaft, and accurately locate TDC using a piston stop or dial indicator. You cannot rely on the notch on the front pulley. The marks on the cams are only suggestions for initial installation and cannot be used for accurate timing of the cams. The closing and opening figures in the manual are for a valve clearance of .5mm (.020"), so you have to readjust the valve clearances on the cylinders that you are using for cam timing to that spec. The mark on the pulley is PM 3/4, or TDC on cylinders 3 and 4. When one is on TDC compression stroke the other is at TDC on overlap. The way to check when a valve is opening is to rotate the valve bucket with a little pick in the notch in the bucket as you turn the engine over. When the clearance had been taken up, the bucket/shim will stop rotating, and you know that the valve is just starting to open. Use the reverse of the same method for valve closing. When the cam just starts to unload the shim, the bucket will free up and rotate. Using the vernier holes in the cam sprockets, you should be able to get the timing within 2 crankshaft degrees.