the conversion is easy in 3 easy conversion steps
step 1, sell what you have for small pile of cash
step 2, empty wallet and bank account onto small pile of cash and make the pile bigger
step 3, take pile of cash and buy the engine you want.
personally, if it was me, I would stick with the bullet proof simple motor you have and get a good estimate for how much fuel you have to add, then add that amount of oil prior to filling up. worst case, you have to add a bit of oil toward the end
