I am on the home stretch of putting new rings, rod bearings, main bearings and timing chain in my 70 472. I have been very meticulous with reassembly however after all of this has been done I find it very, very, very difficult to manually turn over the engine. There are no spark plugs in and I guess at this stage I thought I could grab the crank pulley and turn it with little difficulty. If anyone has some advice I would be very appreciative. Thank you.