Where to place the iris in a barrel lens

[mccolalx]

I'm kind of new to the the actual mechanics of optics, so here it goes...
If i wanted to mount a barrel lens in a shutter, how would i calculate where the aperture blades would be placed?
thanks in advance for any advice

[eddie]

measure the barrel lens and it's iris position. reproduce the numbers for the shutter.

[Doug Howk]

From looking at Kingslake's History of Lenses, the optimal diaphragm location appears to vary depending on lens type. Shutter location is less of an issue for it could be in rear as with Packard shutter. SKGrimes could I'm sure be more specific on a recommendation.