Turbo Height For Gravity Oil Drain

[Maj]

Done several sleeving over the pipe (usually 1.5") but its a bugger getting the flange face flat , last set i machined up spigots , fit was tight on a 750 so butt welded the pipes to the spigot, could put the pipe into the spigot on a busa .
Another thing to consider is converting to external wastegate, those internal gates have trouble controlling the boost levels, internal and external will both need porting of the wastegate hole for increased flow.