i'll actually be in Indianapolis in about 2 weeks. but that's the same engine and just needs a flywheel ?
It should be the same bolt pattern as the motor you have now, the 155 might be a newer version of it?? honestly i dont know, it was on my buddies Pitster pro that is probably about 10 years old at this point. Pitster pro has pretty good customer service, they could advise on specifics of it and would likely have parts.
There is a slight chance ill be passing through Indy in about 2 weeks, i might even be able to meet you at a gas station somewhere... not sure on that yet but could keep you posted. Otherwise your always welcome to come get it or I could ship it to you (granted that would be a bit pricey due to weight).
Figure out if you want to toy with it and Ill dig it out of my basement. im like 90% sure its still down there, i thought i saw it a couple months back.