[Vwdiesel] turbo mount bolt

[mikitka]

I was just going over my head assembly getting things together and cleaned
up for when my turbo comes back, (which hopefully will be tomorrow ) anyway,
I noticed that one of the four mounting holes that goes through the exhaust
manifold is smaller in diameter than the rest. What is the reason for this?
Could it be for an alignment? The shaft of the bolt fit tight in that one
hole but the rest were all loose. Since there isn't any gasket between the
turbo and the exhaust manifold I would think that it is a machined fit and
the openings of both are very close to being exact. Could this be the case?
Just found it odd that it was like this.  

 

Also my exhaust manifold was held on with bolts instead of studs, thick
washers and nuts. Is it a big issue to go back that way or can I just use
the bolts that I took out?

Nick