Op Manual: http://bsintek.basco.com/MDEXResultsPages/PDFDisplayPage.aspx?fileName=lrvvA-wU7eL7hAxB91ObQ

IPL: http://bsintek.basco.com/MDEXResultsPages/PDFDisplayPage.aspx?fileName=Z6nluFVJ1DajI

This IPL should be OK, though it doesn't claim to cover your engine's exact Type Number. BTW, that engine was built on 14th April 1976.

For the drive belt, this past thread suggests an A35 belt, which is a standard industrial belt type/size; https://www.outdoorking-forum.com.au/forum/ubbthreads.php/topics/12545/Scott_Bonnar_Morrison_Model_69.html

But the OEM belts are a 'cogged' type; that would be an AX35, which is better able to handle tight bends around small pulleys.

A Morrison resto thread which has some useful info; https://www.outdoorking-forum.com.au/forum/ubbthreads.php?ubb=showflat&Number=35924&page=all

Cheers,
Gadge

"ODK Mods can explain it to you, but they can't understand it for you..."

"Crazy can be medicated, ignorance can be educated - but there is no cure for stupid..."