He's right all the way. Sorry, I was saying the crisco stuff as a figure off speech but honestly, I've used a dab of vasoline on the rings after installing the lower manifold and I have not ran into any problems but I would use the right stuff made for pre-lubbing a gasket install.
according to the factory manual, section 24-04-12, lubricate new O rings with a light grade oil (the spec called out is roughly equivelant to a light weight engine oil-my comment) or equivelant
NOTE:never use silicon grease, it will clog the injectors
install (injectors) using a light, twisting, pushing motion
I've followed this procedure for almost twenty years now using clean engine oil exclusively without problem one; hope this helps