360 motor mount brackets are different, they can be made to work but are not drop in.

Magnum heads do NOT have 318 ports, they are pretty close to 360 size but way better. You can use old LA valve covers, not perfect fit but you can get them to seal and all 5 LA bolt holes line up. Most aplications I have fooled with putting magnum heads on you have to fool with the altenator to get it to fit mag heads because the heads are slightly longer and the back of the altenator can hit the head. Thease differances asside I highly recomend magnum heads.

The street dominator has great fuel distribution but that is where the performance ends for it, it has very low flow witch should make good tq but the runners are very short and the plenum is big so it is really mis matched within it self.