I've been thinking of cutting some bikes in half for quite a while. I want to create another lowrider. I've built some lowriders in the past, but I was very conservative; I could not bring myself to put a hacksaw to a perfectly good bike frame.
Here is a picture in case you haven't seen it before (It's the same pic as my avatar):

But this was built without sawing the frame in half. The seat was moved aft a good eleven inches.
The fiberglass 4"x6" is strong enough to support the seat without a sissy bar (sissy bars are for sissies anyway). And it supports over 100 pounds in the compartment inside the fairing on the front.

This Redline frame is perfect. Now I can put my fiberglass skills and knowledge to the test.

The way I built the bike in the picture was cheating, because there are still the steel tubes under the 'glass.

I will only use the rear triangle from the Redline. I will get a 20 inch bike for the front end. I think it's going to be a recumbent.

Maybe I should use the Alt bike forum to discuss this further? Or the recumbent forum?