Your right about the 4 outer screws hold the engine to the chassis, the other 4 flanged bolts hold the engines blue mounts to your new K-Factory one piece mount. The chassis is slotted for engine mesh adjustment.once you remove the 4 outer screws, and carb linkage attache
ment, fuel and exhaust pressure line, pipe mount, the engine will be loose for removal. If you remove the 4 flang bolts, you will need to reset gear mesh, thats all they are used for, they do not attach to the chassis at all.