1963 vespa v90, fitting a dr 130 kit

hi, I am wanting to buy a dr 130 kit from sip for my 1963 v90, do I need different engine studs as the old barrel bolts on differently. thanks

Firstly you need to check the cylinder spigot aperture on the engine case. The early 1964 to 1966 models had a narrower spigot. This would mean that you have to machine out the case mouth to the later diameter (as well as purchase the longer studs and later crank for the 15mm gudgeon/wrist pin in the kit.