HEY PAUL YES THE FLYWHEEL IS SLIGHTLY DIFF IN THAT AREA BUT THEY ARE COMPLETELY INTERCHANGABLE , AND THE ENG IS BALANCED INTERNALLY, I JUST FINISHED A TURBO ENG SETUP IN A PICKUP USUNG A STANDARD FRONT DAMPNER AND THE STANDARD AUTOMATIC FLYWHEEL , , AS THERE WAS NEVER A TURBO AUTOMATIC, AND IT RUNS JUST GREAT AND VERY SMOOTH FOR A DSL AND YES ON THE SEAL , WHILE THE FLYWHEEL IS OFF REPLACE THE SEAL , JUST BE CERTAIN AND REPLACE THE LARGE RING THAT GOES BETWEEN THE SEAL AND THE REAR OF THE BLOCK IT IS A SPACER AND IT MUST BE THER OR IT WILL LEAK, JUST PACK THE SEAL WITH SOME CHASSIS GREASE WHERE THE GARTER SPRING IS , SO IT DOESN,T JUMP OUT WHEN YOU DRIVE IT IN JERRY