Bruce, The most popular dye is SEM and is available  at many auto parts stores in aerosol cans. At the chain stores the selection of  colors is limited so go to an auto paint supply house and look at their sample  chart. If you still cannot find the correct color then have the supply house  custom match the dye. (cut a small swatch from a piece of leather or  vinyl that has not seen the sun. Since you should remove the door panels for  a cleaner job, the edge of vinyl or leather wrapped around the back  edge should still look like new)  The Avanti IIs had some unusual  colors, many that are not popular today so finding your color on a shelf  may be tough. The color match will cost you an extra 10-20 bucks over the dye  cost of about $30 per qt. It will be ready to spray. Color matching is  the only way to go if you are trying to duplicate the original color as close as  possible. If you do not have a spray gun, purchase a disposable aerosol sprayer  called Preval from the paint supply or Home Depot about $5 each. The Preval  sprayers give very good results considering their cost and simplicity. You may  need more than one depending on how much you are dying. (ask the supply house if  they can put it in an aerosol can for you. Usually they tell me that the SEM is  too thin and recommend the Preval or professional gun) SEM offers some prepping  solutions to use before you dye. Small cracks and imperfections should be  repaired with a crack repair product and sanded smooth. Also, with leather a  light sanding is recommended to remove any old loose topcoat/dye or small  scratches.
Good Luck, You will be amazed at the results for  the low cost. 
 
Paul Katson
RQ-B 2156 


Werner, Yes SEM is for vinyl, carpet and leather. I  have spoken to a few people that prefer other brands that I am not aware of for  leather but I have used SEM for years on leather with good results and  durability. When dying carpets it should be brushed in to keep it from drying  hard. Light coats and brushing "in" gives the best results but it still ends up  being a little stiff.
 
Paul Katson
RQ-B 2156