Like the tittle says.. can you run a single rec with just 1 power tube to cut the power in half? so i get the saturation i was without all the volume? Is this safe or no?
No. Don't do it. You'll fry your output transformer, and they aren't cheap to replace.
Rectos are a Class AB amp using a push-pull setup. Basically this means one half of the sine wave (signal) goes through one tube - or pair of tubes - and the other half of the sine wave goes through the other tube - or pair of tubes - and the halves are recombined in the output transformer. Since you only have two tubes, you won't have a full signal at the outputs.