fabtech leafspring/add a leaf info

i got 2 fabtech leafsprings, the price was free so im not losing anything if they are no good.
i was told they were part of a fabtech 6" lift kit for a '05+ taco, i was told these used with additional fabtech lift blocks would give a 6" lift.
my question is can i use these as just a add a leaf for my rear leaf springs, i do not have the tsb springs and am completly stock, no lift, right now.
if i can use them how much lift will they provide and what other parts do i need to buy to put them on.
these are the best pictures i can get.
they have a sticker on them but all the numbers and barcode are smudged off, all you can make out is the word fabtech and that they weigh 6.59 pounds.
they are about 30 1/4 inches long
and the arch (if thats even the correct term) is about 4 1/2 inches tall
they have 1 hole in the middle

 

You just need the extended length center bolts. Look on ebay or summitracing.

 

is this what you are talking about? i dont see them on fabtechs site

 

bump, does anybody know if i can use these as a regular "add a leaf" and if so how much lift the will give, and where i can get the new u bolts i will need as well as what size u bolts?

 

Yes you can use them. You can get the ubolts and center bolt from any spring shop, 4 wheel parts, desert rat, toytec, or any other offroad shop.

As for how much lift you will gain its almost impossible to say since there is no idea how much wear they have. You can take them to a spring shop and have them strength test them. If it was me I would just install them and be happy.

This should be a fairly simple install that you can do in the driveway, and only takes a few hours total.