Reverse was at the bottom of the quadrant on a PG but I don't think there is a D1 position. Never saw a D-1 on a PG, P-N-D-L-R. Is L (low) what you are calling D1?

1953 Chevy 5-window 3100
In the Stovebolt Gallery
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Dave
Engine & Driveline Moderator

If you can't make seventy by an easy road, don't go. ~~ Mark Twain