hi guys. does anybody know if its possible to change the camshaft in the small block chevy without pulling the motor? looks like I can if i can get that big chunk of glass out of the way that sits on top of the gas tank and extends into the floor of the cockpit.

I'd take it out personnally. Max 2 hours to take it out, (clean the bilge at the same time) and put it back in 3 hours. now triying to this in place, you know how it works... it supposed to clear, but it does not, loose the bolts, try to move it back and forth a little bit to help you, still not enough, and you end up taking it out...
Or, take off the bolts, but keep wires and hoses plugged, lift as much as possible you can maybe be able to do it half way out. But again, I'd take it out instead of triying this, and triying that... Good luck!

Like Jeff said"take it out". A friend has a 242 and that engine is so far down there it would be hard to ensure a good seal (timing cover to oil pan) while reassembling.