???----You would have to swap the driveshaft.----OR it would be simple to swap the clutch dog and reverse gear.----But what if there is low oil pressure or shift piston is not moving correctly ???----Your location ?
You need to make sure everything is in order.----One plugged main jet and you could be doing the job over again.----After this epic struggle I doubt you want to do that.----Good luck with it.
Take the cylinder head off now.-----Lucky you if it is a blown head gasket.----There is no need to go 100:1 on a motor in good condition.----Bad idea !!
There you go again making assumpions based on poor information and reading.----It is NOT based on a 40 HP motor.-----And changing a carburetor does not turn a 25 into a 40 HP.-----Good luck with your endeavors !
You look at parts and automatically post that you think they are no good / poorly designed.----They built a lot of motors and those 25's are just wonderful !
Not much point in adding oil to the fuel !!-----This is a direct injected motor.-----Agreed , parts support for modern motors is pitiful.-----Too much outsourcing for parts.----Contracts for parts do not exist once shelf is bare.----Costs too much too make short parts runs.-----Easier to get...