RED/BLUE:

01XX59D0

YELLOW:

01XX58D0

No offset in EU until D100

Item 1: any item
Item 2: 8F
Item 3: Lemonade, quantity Pokemon ID in decimal
Item 4: X Accuracy, quantity 88 
Item 5: Carbos, quantity 208
Item 6: Poké Ball, quantity 119
Item 7: Fresh Water, quantity 201

If it doesn't work, add five X Accuracys