It would work by installing the la style heads to the engine just holding them down with a few bolts hand tight. then putting the magnum style intake on top and lining it up as if you were going to install it, putting a bunch of weight on top and/or clamping it to hold it firmly in place, and then lining the holes in the manifold with sleeves with lubrication inside and then using that as a guide and drilling down into the heads. once as many holes are drilled as can be (which should be all except the last two in the way back) while mounted on the engine, take it all apart, use the thread tapper to create the threads, then bolt them all together on a table or watever make sure its lined up right, tighten it enough to keep it stable and drill out those last two holes in the back and then tap them.