Fred,
Two thoughts and one comment;
Thought #1
I got the same T-Stat you are considering. I chose it because of it's high capacity flow characteristics (no
oil starvation issues) and the ability change temps later if I wanted to. Here is a short article on optimum
oil temp from Hot Rod, click here =>
Optimum Engine Oil Temp. When I selected my temp I was not as scientific. I just wanted a temp the was above boiling for water so any moisture would be evaporated and not mixed with oil. In fairness I dod recall reading somewhere that oil should be above the 200˚F threshold for best lubriction. I selected a 215˚ internal spring.
Thought #2
Check out your plumbing diagrams they shipped with the T-Stat. The T-Stat design they use allows for a very simplified addition of a cooler. You only use one line to the cooler and one line from the cooler and they are attached at the to cooler and from cooler ports.
Comment
If you haven't purchased the T-Stat yet when you do and open the box your decision to purchase the Improved Racing T-Stat will be immediately reinforced by the design and quality of the piece. It is also stunningly small so it takes up very little space. If you haven't purchased yet be sure to get their AN hardware. you can't buy less expensively and on the nipples they use a -12 id all the way through to the -10 ORB side so there is nor restriction to the oil flow.
That is a great T-Stat. The longer you have it the more you'll like it.
Ed