Cut a piece of wood 2"x1" the length of the tracks. You can made it 1" or any amount you want to raises it. Just use Long bolts to bolt it back down . Hope this helps.
First, figure out if the cushion is tired from age. I have found putting new padding in a seat cushion will raise me up quite a bit. Otherwise you will need to shim between the floor and the seat track.
If it is the standard coupe seat with the "flip up" backrest there are some adjustments that can be made with the brackets that bolt to the floor pan. Those brackets have different holes in them to move the seat forward or upward. If you have the 'split back' seat then you will need to go with shimming the tracks. Check this website; www.seatrisers.com