help strokeing a 225

Why do you want to stroke a 225. It is not cost effective. Better to bore and use the Weisco/K-1 piston/rod/ring package. Gives a .104 overbore and narrow "metric" ring pack and a long connecting rod. Less then $1,000. See here.
http://www.slantsix.org/forum/viewtopic.php?t=36368

There are several companies that are making good slant six performance parts available.
Deciede what you want from your car, and what you have for a budget, and go from there.