Engine levelers are the way to go. I have an inexpensive one from Duralast that has a coarse acme-type thread that works great. I much prefer it over my nice heavy duty one with 1/2 - 13 threads on the leveling rod, as it operates faster, is lighter weight, and smaller to store in my garage. Use some 1” flat bar bent into an “L” shape with a chain on end going to the leveler, and bolt the other side through one of the removed head bolts with 1/2” grade 8’s. Clevis pins are handy for making chain connections. Just don’t hook on to the intake or exhaust manifold as they will crack under the weight.