Binghams offers templates for different lenght limbs for the takedown longbow limbs. Can you just get the 68" form and make all your different lenght limbs on the same form?
How will that effect weight formulas?

Elmont would be the guy to ask on that,he is real helpful!

I made a couple of shorter ones on the 68" form.  Called Binghams and they gave me the stack height to hit my weight.  Worked well on one at 55# the second was going to be 35# but only came out 20 something pounds.  Not blaming Binghams, just saying.  Kennys advice to call and ask is good.

I called after the advice from Kenny (thanks).
I ordered the 68" plans for the form.

When I ordered the instructional materials for the one I recently made, the sent blueprints for two forms - one for 58" - 62" and one for 64" - 68".

When I talked to Elmont he said you could use the 68" form for shorter lenghts. He said after I get the plans and review the material to give him a call
and he will explain.

Make sure that you call him or email him because he'll obviously give you the answers to your specific questions.

When I spoke to him he said that you'd have to move the index pin on the bow form closer to the limb tip.  If you want a 66" bow, move the index pin 1" closer to the tip (and so on).

He'd give you the best information on what stack you need for the weight that you are trying to achieve if you call him.

Good luck and have fun!