Wooty, here is a recipe that I have used and it turned out very nice. This is for one gallon of juice, so you will have to scale that up to the amount of juice you have. Good luck.
WELCH'S GRAPE JUICE WINE
• 1 gallon Welch's grape juice (red or white)
• sugar to raise SG to 1.095
• 2 tsp acid blend
• 1 tsp pectic enzyme
• 1 tsp yeast nutrient
• 1 pkt Montrachet wine yeast
In a quart jar, activate yeast in ¼ cup of grape juice and ¼ cup of warm water with ¼ teaspoon of sugar and 2 pinches of yeast nutrient dissolved in it. Cover and set aside to develop a vigorous fermentation. Pour grape juice in primary and float a hydrometer in it to determine sugar content. Add sufficient sugar to raise specific gravity to 1.095 (see hydrometer table at
http://winemaking.jackkeller.net/hydrom.asp) and stir well to dissolve sugar and assist sulfites (sulfur dioxide) in dissipating. Add remaining ingredients except yeast. Cover primary and set aside 12 hours. Every 2 hours add ¼ cup of grape juice to the jar of yeast starter. After 12 hours, add activated wine yeast and recover primary. When active fermentation slows down (about 5-7 days), transfer to secondary and fit airlock. When clear, rack, top up and refit airlock. After additional 30 days, stabilize, sweeten if desired and set aside 10-14 days to ensure re-fermentation does not ensue. Carefully rack into bottles and age at least 3 months. [Author's own recipe]