First off, It would have been nice if the block and heads where not machined yet the way they are. I run Cometics MLS gaskets on the majority of the supercharged packages. Did you have a automotive engine builder do this type of machining? A couple things you need to find out so this works well for you- 1.) How much o-ring protrusion do you have? 2.) How deep did they machine the reciever groove and how wide? 3.) What width o-ring wire ? I use a copper gasket with a special graphite water jacket insert on marine engines that are supercharged. I DO NOT recommend the use of the reciever groove! We have done much with this set up in BIG horsepower blown and nitrous engines for Drag Racing. The relationship between the o-ring wire and reciever groove has to be perfect or you could have leakage problem. Let me know if you need the head gaskets. PM me if so. Hope this will help you.