greenhouse Pepper Plants Outgrowing Indoor Greenhouse, Help Please

Hi there again.  This is another help thread, sorry.  As a first year grower, I was not ever sure about starting anything from seed, so I sewed my first round in early January.  I am in the great white north here and did not expect this.  As well, we have had an above average winter in terms of cold weather and snowfall.  My plants are in a greenhouse in a south facing window.  My Caribbean Reds and first Moruga Scorpions are reaching close to the rack of the shelf above them.  It is seeming that they are outgrowing their greenhouse.  It is also too cold outside in the attached garage to store them as well.  Unfortunately it is not even an option of putting them in the window sill or anywhere in the sun outside of the greenhouse due to a very inquisitive feline that also resides here.  Is it possibly safe to trim this bad boy, or would I be better pulling a rack and just dropping the works a level (but I would still need to get it out to water and rotate so it can look at the sun).  Thank you all in advance for any help you can provide.

I feared the same thing starting in February. I figured the worst case scenario I will top them. Then they would branch out from the sides instead. Good luck.
It appears only a couple of plants are problematic, can you relocate them or make room by removal of a shelf? They really would be better off if you topped them when they had more girth in the main stalk to support all the mass that will be produced from topping.
I can relocate them to a shelf lower.  It looks like that would be my best bet as of now.  I am not really scared of pruning, just that I would like to use that as a last resort. 
Great videos posted as well.  I watched 4 of them so far.  I will definitely watch them again before taking the plunge. 
Thank you for the help.