[dsraven]

oh yeah, one other thing, I have seen those concrete blocks used for jack stands many times before but understand that they are brittle and tend to crumble under spot loading. I have seen them fail multiple times in my line of work (firefighter) and had to rescue the injured/crushed worker from under the rubble. please fab up some good strong stands or blocking or spend a couple of bucks on a good set of jack stands. check the local ads or the local pawn shop for a used set. trust me, you will use them over and over in your build. personally I have 3 sets of the large 6 ton stands and a couple of shorter 3 ton stands. I have run out of stands before due to multiple things in multiple places. you will use them if you have them and you can always sell them when you're done if you find they are in your way and you don't need them anymore. check harbour freight for some inexpensive units if the cash is tight but please, never crawl under anything that is blocked up with cinder blocks.