you'll want a torque wrench, angle gauge and some plasti-gauges to set clearances.
you'll need to be able to check for endfloat and bearing clearances. also, you really ought to check the deck height as that could be one reason for the h/g blowing.
a valve spring compressor will be handy.
remember to keep componants in places corresponding to the cylinder they are from. with valves the best way is to get a peice of card, number it 1-4 in and 1-4 ex and poke the valves through it as you remove them. makes it ten times easier putting it back. you'll possibly need a cam timing gauge too, i cant remember with waterboxers.
Jon.