Agree 100% with Jeff you can't leave the engine mounts that way. Assuming you have the right mounts (most likely) my guess is you have interference from the DART SHP block you mention in the first post. The DART blocks have an additional web around the engine mount bolts that aren't on a stock block. Take a closer look and you'll probably see what I'm talking about. Use a die grinder or whatever and notch the motor mount in that location. It doesn't take much and they should sit flat. Tweak the mounts, not the DART block.