351 water pump on 302

You have to change the timing cover too. The 70-up pump inlet will cover the timing pointer on the earlier covers, plus there are two different pre-1970 timing covers. In additon to all this, your harmonic balancer's timing marks are indexed to the pre-70 timing cover pointer (at the two O'clock position vs the 70-up's have a 10 o'clock pointer) And if this all is confusing, the pulley flange offset of the pre 70 balancer is different so the pump pulley will not line up. Then to top all this off, the accessory brackettry is also unique to the pre-70 cover and waterpump. In short, unless you have all the associated parts for a 1970-up pump, stick with the earlier waterpump, mixing this stuff creates more problems than it solves.

actually you don't have to change the timing cover but everything else D. said is correct. i have a 73 351 with all of the 69 accessories including the balncer in the 69 stang.

what i would do is have a radiator shop move the lower inlet to the passenger side, it's an easy job that they can do in hour or so in most cases. we used to do it all the time on v8 z car swaps and stuff like that.

All you need is either two hoses spliced with a short piece of exhaust tubing or a longer hose.