273 dipstick tube length...Dads is...BROKEN!!

Dad bought an aftermarket dipstick and tube and the dipstick is different length than Dads orig one. In my twisted brain, what Im thinking to make or adapt using the orig dipstick is the measurement of bottom of dipstick tube to bottom of dipstick?? Of course the overall length of dipstick would help as well...Lemme all know what ya think??