My new to me 1968 LeMans has a ST-300 two speed automatic transmission. Having some problems with determining replacement amount for fluid changeout for in car as owners manual shows 4 pints (yep pints) and the big Pontiac repair book does not give an amount. We removed 7.5 quarts but transmission was not working properly... slipping big time and no reverse up hill.. We also thought that the dip stick may not be correct but have been unable to find any info on it anywhere as it has a part number 1383413 stamped on the stick. Can anyone give any advise on either one of these issues? Much thanks in advance!