I installed my cast iron bellhousing on my 292 block the other night and checked the alignment of the transmission hole to the crank shaft. The alignment is off by 0.015".

Novak Conversions (which is a great place to go for general knowledge) states that anything over 0.007 or 0.010 is too much and alignment should be fixed using offset dowels.
http://www.novak-adapt.com/knowledge/clutches_etc.htm

Is 0.015" really to much mis-allignment? How hard is it to install offset dowels? Note that this is not going to be a race engine, but will be stronger than stock. Thanks!

My 1958 Chevy Apache 38 1-Ton