Anybody know what size bolts needed for 7.3 exhaust manifold to up pipe (2 each side ) and bellowed up pipes collector (4 total)?
Thanks.

 

The ones at the collector are going to be metric. Don't know what size, but if they're the same as the stock collector, then the Ford dealer typically has them in stock. For the ones at the manifold, they should be pass thru bolts with a nut and washer so anything from the local hardware store should do if you don't mind using a standard wrench as opposed to metric.

 

RiffRaff has them
Riffraff Diesel: Up-pipe Reinstall Hardware Kit 99-03

 

Rob, your PM box is full. Here is the response to your question:

NO gaskets on the exhaust side. You have milled metal surfaces that should bolt up nice and flat against each other. Just check for burrs or irregularities in the surface that you might need to lightly hit with a file.