i have my 70 supported by jackstands under the rear end and stands up front.
i was wondering if im going to have a problem since i only have 1/2 to 3/4 of an inch sticking out of the tailshaft i have plenty stickin in the shaft. with the weight of the car down and the car hitting bumps on the road will i be ok?

I assume you are talking about how much yoke is extending from the tail shaft of the trans? Look at it with the car at normal stance and check the measurement. I believe the norm is 1/2 inch. I bet you will okay, they move but not that much.

I like to have atleast an inch of travel.

Man, mine is 5/8", I was wanting to have it redone to 1/4" for more yoke engagement on the output shaft. Any overtravel would just temporarily compress the dust boot.... (on a TKO)

i have my 70 supported by jackstands under the rear end and stands up front.
i was wondering if im going to have a problem since i only have 1/2 to 3/4 of an inch sticking out of the tailshaft i have plenty stickin in the shaft. with the weight of the car down and the car hitting bumps on the road will i be ok?

You are good to go, 3/4 is nearly perfect:yes::yes::yes:

with the rear axle hanging lose, the distance is shorter than weight on the rear end, so ck it both ways