Slant 6 stroker kit?

Personally, I don't like the idea of a bored and stroked low deck slant. Too much work, and money. Too few advantages. Only advantage is Maybe, a little more RPM then a 225, but not more then a 198 (you use the 198 crank) unless the special piston is light enough.
A 170 starts out as a zero deck motor, so the only way to get a compression increase with a flat top piston is to mill the head, which will give you somewhere between 10 and 11 to CR. A 225 engine can get around 13 to one with common parts, and milling the deck and the head.