Read this from Kirban's newsletter I got yesterday:
[font=]GM AND VICTOR REINZ BUICK TURBO HEAD GASKETS -[/font]
 
[font=]GM and Victor Reinz Buick Turbo Regal head gaskets are one  in the same. The difference is, the ones they made for GM have the GM part  number stamped on them. If you buy a set from GM, you will see the GM part  number and somewhere a small “v” stamped in a circle somewhere on the  gasket![/font]
 
[font=]I actually talked to a person who had access to the  records and tooling for GM for the 1986-1987 Turbo Regal head gaskets, which GM  ordered back in 1985.[/font]
 
[font=]Victor Reinz made the original head gaskets for the  production 1986-1987 Turbo Regals. There are two different part numbers, both  will work from Victor Reinz for the 1986-1987 Turbo Regal engines.  [/font]For over 20 years Richard Clark has used  both numbers with zero issues. He has built several hundred 1986-1987 Turbo  engines using the same exact gasket we sell.
 
[font=]He originally found this information out years ago from  his local GM dealer. One format has a small extra hole in the head gasket that  actually sits outside the head and does nothing. The other version does not have  this extra hole that is not used. Both versions are 100% the same except for the  one exterior hole.  [/font]Our part number  is #7576 and we sell a pair for $54.95 plus shipping. The list price is almost  $90 a set.
 
[font=]The end result is the Victor Reinz head gaskets and GM are  exactly the same. The real difference is what price you want to pay for a set of  head gaskets.[/font]
 
[font=]We usually have the version that does not have the extra  hole in stock.[/font]
 
[font=]Either version is getting increasingly difficult to get.  Most manufacturers that have GM as a client make the same part, but leave off  the GM part number for obvious reasons.[/font]