I bought a 3 grand stally to mate up to my clevo and yesterday i went to bolt the whole lot up and realised that the stally has come from a windsor engine. it has obviously been a modified convertor as you can see where the original bolts go (and where they need to be for mine)

however i need to get some bolt welded into the "half holes" that are only left, and i was wondering if having the bolts welded professionally will be adequate?

it appears they have redrilled bolts closer to the centre to suite the windsor and have had the edge of the convertor machined?

anyway i hope the pic clarifies things.

Redrilling the flex plate might be an easier way to do it? Measure distance from centre of converter to the bolts, and do the same on the flex plate and mark it.
Drill the new holes inbetween the old holes (ie 45* apart from the old holes) else it may crack inbetween the two if you did it directly under