Is it essential that I position piston at TDC when replacing water pump?
 

My 95 Integra is leaking coolant, I'm pretty sure the water pump has failed so I'm replacing it myself. The only thing is, I'm having trouble locating TDC, but it occurred to me, is it absolutely necessary to put the #1 piston at top dead center? If I don't move the crankshaft any when removing the timing belt, then I should be ok , no? I don't see why the Haynes manual says it should be at TDC for installing a new water pump.