Later .3s, .4s, .5s, and .6s have the starter on the other side. Unlike a .3/4/5 the .6 does have a removable bell housing. Remove the bell housing from the .6, chop it down, chop the end off a sacrificial 617 .3, tig weld together. It could be done.

I thin whipplem104 offers a stand alone .6 controller.

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