i guess it would be better for you to purchase the backplate for v-one-s only.
[back plate=the plate use for covering the conncting rod, if u don't use the pullstart]
but i don't know if the LHS near you sell it.[it is not in indonesia]
i got a case precisely just like you, but it's happen to me when i own the stadium truck nitro sport....from TRX
the original engine is broken [conn rod is broken
] so i replace the engine with "force" .15 engine w/ pullstart, i don't know wether the price is cheap or the pullstart quality's bad..
the pullstart broke in one night when i tried to break in the engine
.....but if you want to replace your engine with another brand, may be you should choose the one without the pullstart, it would be better to use those starter box...
BTW do you have a starterbox?