If you get into doing this any way other than the correct way... which it to get all those bolts set up properly you will eventually be unhappy. Some other fix may work for a short time but will likely not work for long. Especially on exhaust manifolds where you have very high heat.

I know you have been trying to avoid taking the engine out. But it isn't really that big of a deal as long as you have someone to help you and it will make this much much easier. Then you can do it right. And you can get a good look at all kinds of other things very easily while its out. If nothing else to some good cleaning and lubing. I think you will be happy you did. You can probably rent a lift and an engine stand is not expensive. And you an sell it when your done.