Differences in bumper jacks

[rr440EW1]

What is the difference between a "T" shaped mast jack and the "tube" style mast jack assembly? Are they just from different vendors or are they for different applications?
I am specifically interested in info to be able to ID the correct jack for a '70 B body (70 Super Bee).

 

[rr440EW1]

I'm surprised that there is no one that can help me out on this subject.

 

[69 Runner]

Dunno. I've had cars that have had both (obviously not at the same time). Most of the B bodies I've owned (that still had the original jack) had the "T" type. But most of the B bodies I've owned (probably close to 15) were St. Louis cars. That in and of itself doesn't prove anything.

I didn't see anything in the White Books about the masts. However, if there were part number information on the BASES, then it might be possible to narrow it down.

 

[rr440EW1]

Dunno. I've had cars that have had both (obviously not at the same time). Most of the B bodies I've owned (that still had the original jack) had the "T" type. But most of the B bodies I've owned (probably close to 15) were St. Louis cars. That in and of itself doesn't prove anything.

I didn't see anything in the White Books about the masts. However, if there were part number information on the BASES, then it might be possible to narrow it down.

I checked the GG white books also. I don't recall ever seeing any articles about this subject.
My cars have had the "T" type jacks. My cars have been Lynch road cars.