This could cause a lot of problems. First, if there is an offset angle (right thrust) built into the firewall you will have reversed that and have the angle to the left. This could cause the plane to fly weird because the offset will now be set to the left. Second, with the carb so low you will more than likely have a lot of problems with fuel siphoning through it. Third, looking at the position of the engine at the spinner plate it looks like the engine is not centered in the cowl.

If the firewall is flat and doesn't have a thrust angle built into it then you have an easy fix. Simply epoxy dowel rod into your existing mounting holes in the firewall and drill new mount holes in the correct position. Then you can mount the engine correctly. If there is a thrust angel built into the firewall you can still redrill new mount holes, but you will have to shim the engine mount in order to get the thrust angle correct.

Ken