I use dremel tool with thin cut off wheel to modify Japanese Industrial Standard screw on carb drain screw to accept old fashioned blade or number 2 phillips screwdriver . Inelegant but effective. Cross-cut head of JIS head about 2 or 3 mm and do not over-tighten."I had a VERY difficult job getting the shorter of the Phillips head screws loose,"
Please remember that there are no Phillips head screws on a TW. They are JIS screws and really need a JIS bit to fit correctly. If you don't want to buy a JIS screwdriver set then use the screwdriver in your tool kit.