Is changing the valley seal and rocker gaskets a big job as I have an oil leak and cant find where it is comming from done sump gasket. only leaks when parked on a slope facing up or down If parked on flat it dont leak
its not hard, half a day ish. just dismantle the top bits and you will see it. the intake manifold and above needs to come off. you should be able to get the plenum to move enough to on side to get in.
when you put the intake back on put all the bolts in and tighten em each a bit at a time as it can be a bit arkward to get it to sit nice and straight. its heavy too when your stretched over so get someone to help position it with you!