Wanting to change original 1200 36hp to later model motor.New one has 180mm fly and clutch,will this just bolt straight to existing trans or will I have to grind trans housing?
Also I could get an IRS box to couple to the new motor but would this fit straight into a '59 swing axle beetle?I dont want to go IRS suspenion though.Cheers for any thoughts.

Depends if its a 6volt 180mm flywheel or the later 12 volt 180mm used on the 1300Twin Port.......do you know which one it is ?
Is your car still 6volt ?
If its a 12volt you will need to grind the trans housing in a few spots to make it fit.

Re the IRS box, no it won't fit straight into the 59.

Thanks Craig,not sure if 6v or 12v,but more thinking thats it is 12v as it is a TP.Car is converted to 12v but still running 6v starter,realise I will have to change that and bush if the fly has 130 teeth,thanks for the heads up on the IRS box and the rest of the info.