You need to check the block designation, and the head designation. Some parts can be swaped in that manner. You also need to check the type of piston you are using, and the valve geometry to make sure there is no parts contact.
Compression ratio is also going to be an issue, as will be the pushrod and rocker arm configuration. This is a swap best left to a really good mechanic unless you line up the parts through a good shop.
I'm not going to blow any GM web sites horn since there are so many out there. Just look for a nearby shop that has a web-site, and tell them what you have, and what you are looking to end up with. It should not take long, but may end up costing quite a bit.