That sort of depends on whether you have the right pullers, etc. One engine i saw had the oil pump drive beaten to death because the person didn't have the right puller. Now, the person that owns that cart has to mix their gas/oil instead of having the pump/regulator doing that for them. Then there's the drive pulley. If you don't have the right tools, you can save yourself some money by pulling the engine from the cart and taking it to someone that has the right pullers. Let them install the seals, then you can reassemble the engine and reinstall it into the cart.