[stuntman703]

I'm on the market for a new thermostat. Why...long story of me knowing nothing about these cars before purchasing one (probably an air bubble).

Here's the DL though, '84, going over old receipts, I have an updated WP
(95110602110), and with that the owner also bought the thermostat, seal and shim washer (I have the part numbers as well).

Here's the kicker though, the gap from the seal to the snap ring is 4.5mm so I would think I need to purchase the stat for the old style pump (944-106-129-05-M2) but on the receipt it has the new style stat (944-106-019-00-M2) fitted with the thin stat seal (944-106-929-05-M2).

Is there a difference in their mechanics or temperature? I also dont ever remember seeing a metal shim when I removed the stat a long time ago.