Topping off tomato & no. of trusses?
So I'm very pleased with my first years attempt, my plants are all bout 5-6ft high right now and have green toms on. I've read a bit of contradictory comments on topping off, some seeming to put it in a negative light. My greenhouse is only a little over 6ft tall, however I could try and train them up the roof to the middle, is it okay to just chop the tops of the stems off when they're 6ft, or should I try and let them grow taller?
Trusses wise, some seem to talk about limiting it to a certain no. per plant, is this necessary or can I let them just make as many as they produce, but potentially have slightly smaller tomatoes? (the one with the most has 7 trusses atm, albeit not all bearing fruit).
(I have been pruning side shoots though have let them all have two main stems)