Dyeing cloth seats -- anyone have experience?

[Jpinkowish at aol.com]

Hi Folks,
Has anyone tried dyeing their cloth seat covers to restore the original 
color?  I'm toying with this for the gray cloth covers in my '85 4ksq.

Does anyone know what fiber(s) are used in the seat covers -- nylon, 
polyester, nylon/polyester blend?
--product(s) used? procedure(s)?
--covers on/off the seat foam?
--results: uniformity of coverage, removal of excess dye, rub-off?

Is this foolish idea?

Jan Pinkowish
'85 4ksq
Bristol, CT