2003 Specialized Bighit with boxxer 888???

All the world's puppies will die if you fit a Boxxer 888 to that frame...

Would prolly take a look at some of the fork manufacturer's sites before I would post to much more, if I was you.
Those frames are best suited to forks around 170mm although they work sweet with a 190mm Shiver also as it has a low axle to crown height.

I've never even heard of a Boxxer 888.

I've put a 2008 Marzocchi 888 ATA WC on my 2003 Bighit Expert, but then I also have a 26" rear wheel. It's absolutely unbelievably good. Don't know what it'll be like if you still have the sstandard 24" rear wheel.

Ive seen a ton of the older Big Hits with 888s. You should have no problems.

So are you asking about the boxxer or the 888? I'm confused with your question...