Just looking for some basic info to help in my search for an engine for my ‘67 LIL Indian mini bike project. I understand that the original Briggs & Stratton engine model for the 3HP LIL Indians is #80212. I’ve come across similar engine models such as the #81232. They’re pretty identical in appearance but I believe the standard model (80212) uses the Kool bore cylinder. Not exactly sure what this is but is it preferable? Whereas the model 81232 has a ball bearing flange mount which may be superior but perhaps uses a steel cylinder? (not sure what the second digit “1” designates in the overall model number). Any thoughts on these differences? And lastly, do most B&S equipped LIL Indians have 3/4” driveshafts? Or was 5/8” offered as well? Any advice greatly appreciated as I’m still very new to this hobby. Thank you.