I did that conversion on my Tiger. Was dead easy - had to drill 2 holes per gudgeon casting (4 of the 6 bolted straight up). Just a word of warning, check the bolts/nuts are tight periodically, one of mine worked loose and allowed the gudgeon casting to move ever so slightly which was enough to end in catastrophe at the worst possible moment. I epoxied the bolts in with the repair and have had no problems since

Michael