I have a 68 Impala with which there was originally a 327. Previous owner did a great deal of work to make her a Super Sport including either a 427 or a 454. I need to replace the starter which was not straight forward as the cone was too short and bendix gear does not engage the flexplate. So...looking for all of the details on the engine. So far 3963512 on block, T1203CRN on passenger front block and VOL156023 or possibly VOL456023 on the block driver's side by transmission flange. I also found 1T on a small flat pad below the driver's side valve cover, HIPERF PASS1 with K Driver's side and finally the number 5 stamped on the starter pad. Any help with ID would be greatly appreciated!