30 wt
Any straight 30 weight should do.
5w30
Sae 30w
SAE 10w30 full synthetic any major brand.
SAE 10w30 all year round or SAE 30 if it is only used in the summer. Use 100% Synthetic oil in this air cooled engine.
If the lawnmower has two compartments one for gas and the other for the oil, then put gas in the gas and a 30w type oil in the oil compartment. Simple as that. If you have an engine with only one compartment then you'll need to check on the manufacturers suggestions which is usually 40:1 or something close.
electricity
Most professionals recommend that you use high octane gas. Like 92-94 octane.
Get a Craftsman torque wrench and make sure you get a warranty. There have been some complaint of problems with the wrenches. Craftsman is probably correcting the problem so that means you should end up with a goood tool.
"6.6 craftsman " is insufficient info. -If you expect a sensible answer, please describe it fully.
What kind of engine? lawnmower, car.