Recently dropped a 99 expo 302 in my 99 ranger, ran when I did and after replacing intake manifold due to leaking coolant it won't fire, new plugs, new cam sync set at tdc when installed diagnostic computer reads extremely lean

Any chance of a forgotten vacuum hose or missing disconnected ERG valve?

Are the injectors, coils and TPS wired correctly?

Fuel pressure correct?

Upper to lower manifold gasket properly located? Those are easy to get out of alignment while getting the upper intake into position.