There are many Nice
high quality bike motor kits out there that require very little skill and very basic hand tools that everybody should have..
GEBE ( golden eagle )
staton
Dax Titan
Bike motor parts
Dimension edge
For example a GEBE system can be installer in about a hour with just a screwdriver and crescent wrench...
Choosing a good bike is just as important as choosing the right engine...
V brakes !!!! Good tires not stock ones!!! Strong wheels !!!! 26 inch bikes work best...maybe suspension if you ride on rough roads..provisions to carry extra fuel... A good light...a speedo... Good high quality seat is a must ...
And Laws !!! Don't waist your money to find out the police won't allow you on the streets...
And also keep in mind the the MB laws are kinda iffy to say the least.
In my state they are legal , but your local police dept. Can say no !!!
So instead of just trusting the state law.. Ask some riders in your area and if there are none ask a local cop ..