Originally Posted by Rough-Rider
hey guys...i have another question, im wondering what kind of modifications will have to be done to the 350 heads besides drilling the 7/16 bolt holes out to 1/2" to fit on my 403??
thanks for the help!
i beilve that would be it...
You may want to check out www.oldspower.com
there are some persons with that same combo, they could probably give very detailed descriptions there.