I believe this dip stick is for a 70 GS 455 NO POWER BRAKE 1230489. Please check the part number for yourself for correct fitment...…. Asking $ OBO SOLD Thanks. .
This is quotes from other members conserving the 1230489. I believe what I posted is correct from my research. Thanks “being manual brake equipped, may be absolutely correct with the #1230489 non-adapter style gauge rod. Being that the 1970 assembly manual fails to specify the car series, it is entirely possible such installation occurred on the assembly line.” “Pics below are of my 10C, 3rd week of Oct 1969, 70 GS 455 4 speed car with no oil dipstick tube. Note, that this car is all original, untouched ,unmolested manual steering and manual brake car.” “So it seems manual brake Big Block GS cars in 1970 received regular big car oil dipstick. Stage-1 cars”
I posted what is printed in 11/71 Buick Parts Manual. "69 430 Eng" "70-71 455 Eng. exc. 30-4000" 1230489 is the part number for the Oil Gage Rod that is listed and illustrated in the '70 Assembly manual. I hope this helps.