If I may, I think you're trying to move it the wrong direction. Instead of moving the engine forward, why not down instead? If you make your own motor mounts, you should be able to lower the whole thing a few inches. There should be plenty of room for the suspension movement afterwards, and you can tinker with the T-case crossmember however needed to get everything sitting at the right angle. I believe the headers will still clear just fine, as they loop up plenty high for clearance as it is. Just a thought.