[burnin oil]

There is a little more going on than just drilling and tapping the head. Can it be done, yes. The problem is that you don't address valve installed hieght or spring pressures. If the motor is stock than you will probably get away with it since the cam lift is usually pretty mild. It may be money ahead to see if any local machine shops have a set of heads they want to get rid of cheap. Alot of times people will leave them for whatever reason and the shop will sell them cheap to recoup their money.

For the cam timing issue you will need a new timing chain. It should come with the chain and 2 gears. You will remove the balancer, water pump, oil pan and timing cover to install it as mentioned above. I personally locktite the cam bolts and the balancer bolt to keep them from coming loose. Its cheap insurance.

The distributer will rotate at half the crankshafts speed. This is because the cam gear is twice the size of the crank gear. Look for delay when rotating the crank back and forth. Badically rocking it. This will tell you the slop in the timing set. It generally takes alot of slop to let it jump time. There is a little slop in a new chain usually.

If you don't pull the motor down to the timing chain you will need a poston stop to figure out where TDC is so that you can correctly time the motor. If the chain has jumped it will do it again.