cj6 questions

I have a 1966 cj6 with the 225 buick dauntless v6. I lost my husband recently and he was just starting to work on the jeep. I want to continue with the project and I was hoping to get some guidance along the way.
I want to change the oil and want to know what is the best oil to use for it?
I need an air filter cover?
And finally, can I flat tow this jeep because it has hubs?
Any help is greatly appreciated.
Thank you Karen

I would use 15w30 valvoline oil, if your going to flat tow, remove the drive shafts first, that way you wont damage the drive train