Within the next couple of weeks or so, I will be changing out my manifolds to an Offy 4 bbl and dual exhaust. Since I have a small oil drip from the right (passenger) rear of the head, I thought I might change the head gasket when the manifolds will be off and all the carb linkages unhooked.

The engine is bored 60 over. Will I have to trim the gasket to make it fit? What is the best gasket to use, and do you seal it with ATV Copper?

It is my impression that the Australian GPRS gasket makers have head gaskets. If I order one from them, what do I give them for the measurement of the piston holes?

This will be the first time for me to remove the head off of a Slant. Any other advice you would like to give me would be welcome.

A standard "composition type" gasket is the way to go when dealing with "you must clean it" surfaces. The bore size on these are 3.5 so you will have no problem using it on a 3.46 bore.

Are you sure the oil leak is from the head gasket and not "trickle down" from the valve cover or spark plug tubes.

As a general rule, if I go through all the work to pull-off the head, I would want to do a valve job while it is off, even if it is just to touch-up the seats and put on fresh valve stem seals.
DD

I've been watching, thinking it has to be from the valve cover or plugs tubes, but it doesn't really appear that way. However, I am going to replace the tube seals and valve cover gasket this weekend, just to make sure.

If I do change the head gasket, does somebody make a better composition gasket than the others, and what sealer is the best to use.

on a head gasket you don't really need sealer but if you want you can spray it down with some copper spray or I found this really good stuff made by permatex called indian head that works awesome I have not used it on a head gasket yet but I use it on all manifold gaskets (I tried it on my hotbox that would not seal and my collector gasket that would not seal and it worked great) I will try to get the part # off it when i go home tonight

If the valve cover comes off, try re-torquing the head bolts and check the valve lash adjustment. (Do both with the engine hot)
DD

Will do. Thanks DD!