The last post doesn't seem to gel with the original in not wanting to spend big $$.
I think if you start adding SVO heads you are in for a much bigger (read $$) project, not only is the intake manifold choice more limited, you will require those raised exhaust port headers.
Many people epoxy injector bungs, but it should be relatively cheap to have them welded by a competent shop. Most cast aluminum manifolds don't have a lot of extra meat for welding either, so this really is a job for competent shop who has done it before and can set them all correctly at an appropriate angle and depth.
I had this guy www.hotrodsolutions.net bookmarked from a recommendation somewhere (I forget where) but looking through his photo's would appear to be pretty competent.
Julian
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