It's always handy to have a whole pile of scrap wood around while you are fitting engines. There is no other way to do it that I can think of. It's easily cut down to length, you can use all sorts of different thickness's and it's relatively soft so it won't scratch or dent your nice engine.
I am NOT leaving the oil pan this high up off the crossmember at all.. but this shows how nice it is to have the different thickness of wood to play with.
Here are all sorts of different sizes of wood that I but down really fast to make sure the engine was sitting level as possible while test fitting things. It worked out really nicely.