My trek 850 project
 

I recently pick this Trek 850 for $10 and a Bianchi strada hybrid with a Bend frame for $10 also. I'm going to used the components from Bianchi and swap it to the trek 850 frame.
Just wondering how this frame will feel with 700c wheel setup vs 26 MTB wheel?

I'd guess it would feel somewhat similar. Elements of geometry won't change that much, but the bottom bracket is likely to be higher.

Assuming you can salvage the fork and headset (not guaranteed; the Trek may have a bigger headtube), your biggest problem is going to be fitting the brakes on the back end. Unless you have mad fabrication skills, you'd need at least one of these - https://www.biketrailershop.com/xtra...er-p-1600.html