The 304 has plenty of poop to pop axles, it comes down to the driver and the trails, crap did I just say that.
Yup, I've broken d44 F&R axles with TBI 304 been on my lid a few times too. If the hot rodder in you has to have the put you back in the seat performance, you might as well get your EB back cause the MPG with a hot rodded 304 or 350 will stink.
Keep the 304 and 2bbl until it explodes.

SD