I love the plate!
Something to consider: You need to be very careful how you use concrete blocks to support heavy objects such as vehicles. The block located at driver side rear is offering little strength in its current position. If you suddenly loaded that block it would crumble instantly. I like to stay away from using that type of block but if it is all you have do the following:
Make sure the block is laying flat (picture it the way it would be installed in an actual wall) take scrap 2x8 or 2x10 whatever you have and lay it on top. This will help distribute the load over the surface. Also make sure the bottom of the block is making contact along its entire face. No pressure points!
Sorry for the lengthy post, just want you to be safe! When I need to block up, I have a bunch of 6x6 leftover PT stock in various lengths. They will even hold up my 20+ thousand pound Mack! (with a piece of C channel across the top to distribute the weight)
Good luck with your project and make sure you get it done before you have kids!